The appellant, Dennis Hall, was convicted by a jury in Barrow County of the murder of his ten-year-old son Adrian, of two counts of cruelty to children, and of discharging a firearm near a public street. He was sentenced to death for the murder. He appeals. We affirm.
1. During his marriage, Hall’s alcohol abuse and abusive behavior towards his wife and three children resulted in numerous occasions in which the police were called to restore order to the household. Hall once locked his family out of the house when the outside temperature was below freezing. On another occasion, his wife told police that Hall had struck her in the head with a pistol. He also once threatened to shoot his wife and fired a shot into the air. On none of these occasions, however, did she press charges.
On Sunday, January 7, 1990, Hall began drinking early in the morning and drank throughout the day. As Hall watched television that afternoon, his son Adrian played with a toy remote-controlled tractor. Hall told Adrian to stop, because the toy was interfering with his television reception. When Adrian did not cease playing immediately, Hall went to the boy and struck him in the head. This precipi*779tated an argument between Hall and his wife concerning the necessity for the severity of Hall’s punishment. Hall responded by searching for his shotgun. His older daughter took the shotgun outside and hid it in the car. Meanwhile, Adrian got the pistol and took it outside. Hall found the shotgun and loaded it while his wife tried unsuccessfully to take it from him. He approached Adrian, who stood 10 to 15 feet away saying, “Don’t shoot me, don’t shoot me.” Hall shot him in the chest as his wife, two daughters and his next door neighbors looked on. Hall went home, but returned a few minutes later to Adrian’s body. Hall kissed his deceased son and told him he loved him. When his neighbor suggested it was “a little too late for that, you’ve done killed him,” Hall responded, “Shit happens,” and bragged, “I couldn’t learn him nothing by beating him with a belt, so I guess I learned him something this time.”
A test administered later that afternoon showed that Hall had a blood alcohol level of .32 grams percent. All who observed Hall that afternoon, however, testified that he was not overly intoxicated, was steady on his feet, and had only slightly slurred speech.
In a post-arrest statement to police, Hall claimed he shot his son in self-defense. Later, he claimed it was an accident.
The evidence supports the conviction for murder. Jackson v. Virginia, 443 U. S. 307 (99 SC 2781, 61 LE2d 560) (1979).
2. In his first enumeration of error, Hall, who is black, raises an issue under Batson v. Kentucky, 476 U. S. 79 (106 SC 1712, 90 LE2d 69) (1986), concerning the prosecutor’s exercise of peremptory challenges. Noting that the prosecutor used six of his ten peremptory challenges to strike all six black prospective jurors on the qualified venire, Hall argues he has established a prima facie case of purposeful discrimination in the selection of his jury. See Batson, supra at 96. The state concedes this much (state’s brief at p. 14), but contends it successfully rebutted the prima facie case by articulating race-neutral reasons for striking as it did.
After listening to the prosecutor’s explanation of his peremptory challenges, the trial court stated that it was concerned only with the prosecutor’s final peremptory strike. The other jurors were struck either because they were well acquainted with the defendant and his family, were closely related to persons who had been in trouble with the law, or had expressed a reluctance to impose a death sentence. See Foster v. State, 258 Ga. 736 (2) (374 SE2d 188) (1988). The final black juror struck by the prosecutor knew the defendant’s mother. Moreover, the prosecutor had prosecuted her cousin. Nevertheless, the prosecutor explained that he had-planned to save his last strike for a white prospective juror who had once been arrested on a “bad rap” and had “bad feelings” toward the judicial system. However, on the morning of the jury selection, the last black juror entered the *780courtroom with the defendant’s family and sat immediately behind the defendant’s mother. The prosecutor stated that when he learned of this, he decided to exercise his last peremptory strike against the juror.
(a) The defendant, noting that no one observed the juror actually talking to the defendant’s family, contends the prosecutor’s explanation was insufficient to support his final strike. However, as we have explained, the prosecutor’s explanation “ ‘need not rise to the level justifying exercise of a challenge for cause.’ ” Gamble v. State, 257 Ga. 325, 327 (357 SE2d 792) (1987) (quoting from Batson, supra). A reasonable suspicion about a prospective juror’s impartiality that falls short of justifying an excusal for cause might well justify the exercise of a peremptory strike. This is such a case. That the prospective juror entered the courtroom with the defendant’s family and sat next to them might have been mere coincidence, but there was at least some reasonable likelihood that it was not. We cannot condemn the prosecutor’s reluctance to gamble on the significance of this occurrence.
(b) Pointing to the trial court’s explanation that if the prosecutor could “articulate nonracial reasons for the strikes, he’s entitled to exercise” them, the defendant contends the trial court failed independently to evaluate the prosecutor’s explanations for his peremptory strikes.
Of course, the trial court may not simply give “rubber stamp” approval to “all nonracial explanations, no matter how whimsical or fanciful.” Gamble v. State, supra at 327. The explanations must be sufficiently persuasive to rebut the prima facie case. But we do not read the trial court’s extemporaneous remarks so parsimoniously as does the defendant. The record as a whole demonstrates the trial court’s understanding of its role under Batson.
(c) As we noted in Gamble, supra:
A court charged with the duty of determining whether the prosecutor has rebutted a prima facie case may be less troubled by one relatively weak explanation for striking a black juror when all the remaining explanations are persuasive than where several of the prosecutor’s proffered justifications are questionable. Similarly, a weak prima facie case may be rebutted more readily than a strong one. [Id. at 327.]
In contrast to the Gamble case, where the defendant was black and the victim was white, here both the defendant and the victim were black. Moreover, unlike the Gamble case where several explanations were suspect, here the trial court was concerned about the sufficiency of only one of the proffered explanations. The trial court in this case was authorized to conclude that the prosecutor had successfully re*781butted the prima facie case.
3. There was no error, as the defendant contends, in the pre-trial excusal of four prospective jurors who were college students enrolled in schools outside the county. The trial judge specifically authorized these excusáis for “other good cause” under OCGA § 15-12-1 (a). (Their service was deferred to a later term. Ibid.) Hendrick v. State, 257 Ga. 17 (2) (354 SE2d 433) (1987).
4. There was no improper restriction of the death-qualification voir dire. It is not “permissible to ask a juror to describe the kind of case that, in the juror’s opinion, would warrant a death sentence.” (Emphasis in original.) Blankenship v. State, 258 Ga. 43, 45 (6) (365 SE2d 265) (1988).
5. The defendant next contends the trial court should have granted his motion to excuse for cause a prospective juror who admitted having an opinion about the defendant’s guilt. The juror, however, testified that he could set aside this opinion, accord the defendant his presumption of innocence and decide the case on the evidence presented at trial. The trial court found that the juror was qualified. This finding is not clearly erroneous. Spivey v. State, 253 Ga. 187, 196-197 (319 SE2d 420) (1984); Waters v. State, 248 Ga. 355, 362 (2) (283 SE2d 238) (1981).
6. Previous difficulties between the defendant and his family were properly admitted to show the defendant’s bent of mind towards the victim. Wright v. State, 184 Ga. 62 (8) (190 SE 663) (1937).
7. In his 6th and 7th enumerations of error, Hall (a) complains of the admission of testimony by two social workers about the possible effects on the defendant’s two surviving children who witnessed the murder of their brother by their father, and (b) contends that the evidence is not sufficient to support his conviction on two counts of cruelty to children.
(a) The evidence is undisputed that the defendant’s two surviving children were present and witnessed their only brother being murdered by their father. The two children, however, do not presently exhibit overt manifestations of having been traumatized by the event. In fact, according to defense testimony, they showed great affection for their father when he appeared at the victim’s funeral (in the custody of law enforcement officers).
The first social worker testified that she is a caseworker with the Barrow County Department of Family & Children’s Services. In her 16 years of service, she has worked with several hundred victims of abuse and trauma, including children who have witnessed siblings being seriously injured or killed. She testified that many such children repress such experiences and show no immediate outward signs of trauma, but that it often emerges years later.
The second witness is a licensed clinical social worker and thera*782pist. She testified that she would expect unconscious denial from a young child who witnessed the murder of a sibling, with no outward symptoms until the child was older.
Hall argues that the testimony was irrelevant because it described possible future trauma and not what the children experienced on the date of the murder and was otherwise inadmissible because the witnesses were not experts, and their testimony was speculation.
An expert witness is one who from education, training or experience has peculiar knowledge concerning some matter of science or skill to which his testimony relates. The qualifications of an expert are addressed to the sound discretion of the trial court. Taylor v. State, 261 Ga. 287, 290 (13 a) (404 SE2d 255) (1991). Expert testimony is admissible where the conclusion of the expert is one which jurors would not ordinarily be able to draw for themselves and where such testimony would be helpful or necessary to assist the jury. Jones v. State, 232 Ga. 762, 764-765 (2) (208 SE2d 850) (1974).
The defendant was charged with “maliciously causing] . . . cruel and excessive mental pain” to his two daughters (three and seven years old, respectively). See OCGA § 16-5-70 (b). The expert testimony was not offered by the state to establish conclusively that the two children had suffered cruel and excessive mental pain, but to counter the anticipated defense contention that, because they exhibited no overt manifestations of trauma, they had not experienced cruel and excessive mental pain. The expert testimony was properly admitted by the trial court.
(b) The jury was entitled to conclude beyond a reasonable doubt that the defendant’s two daughters suffered “cruel and excessive mental pain” when they watched their father murder their only brother. OCGA § 16-5-70 (b). Moreover, the jury was entitled to conclude that the defendant maliciously caused this pain by wantonly and wilfully shooting his son “with an awareness of a plain and strong likelihood that such harm may result.” Rigenstrup v. State, 197 Ga. App. 176, 180 (4) (398 SE2d 25) (1990). The evidence supports the jury’s verdict on the two counts of cruelty to children. Jackson v. Virginia, 443 U. S. 307 (99 SC 2781, 61 LE2d 560) (1979).
8. In the circumstances of this case, the defendant was not entitled to an instruction on either grade of involuntary manslaughter, OCGA § 16-5-3, or on accident. Binns v. State, 258 Ga. 23 (2) (364 SE2d 871) (1988); Flanders v. State, 188 Ga. App. 98 (2) (371 SE2d 918) (1988). Beck v. Alabama, 447 U. S. 625 (100 SC 2382, 65 LE2d 392) (1980), does not, as the defendant contends, mandate instructions on lesser offenses not supported by the evidence. Hopper v. Evans, 456 U. S. 605 (102 SC 2049, 72 LE2d 367) (1982).
9. The court’s instructions concerning inferred intent were not erroneous. Isaacs v. State, 259 Ga. 717 (35 B) (386 SE2d 316) (1989).
*78310. The defendant argues the state should have been compelled to disclose the criminal records of its witnesses. The state claims it is not aware of any such convictions. The trial court did not err by refusing to compel the disclosure of that which apparently does not exist. Compare Isaacs v. State, supra at 723-724 (11).
11. The § b (7) aggravating circumstance authorizes the death penalty where the offense of murder is “outrageously or wantonly vile, horrible, or inhuman in that it involved torture, depravity of mind, or an aggravated battery.” OCGA § 17-10-30 (b) (7). This circumstance has two parts. First, the murder must be “outrageously or wantonly vile, horrible or inhuman.” These are words of common understanding having essentially the same meaning and are intended to help distinguish non-capital murders from those in which a death sentence may be appropriate. Hance v. State, 245 Ga. 856, 861 (268 SE2d 339) (1980). Second, the offense of murder must involve either torture, depravity of mind, or an aggravated battery to the victim (or a combination of these three elements). Id. Accord West v. State, 252 Ga. 156, 161 (Appendix) (313 SE2d 67) (1984).
The jury returned this verdict:
We the jury find the following statutory aggravating circumstances to exist beyond a reasonable doubt: wantonly vile, depravity of mind, horrible, inhuman in that it involved torture.
The defendant contends this verdict is not a valid finding of the § b (7) circumstance. We disagree. Although the verdict’s word order does not track the statute exactly, the verdict includes all the essential elements of the § b (7) circumstance and all the findings necessary to sustain a § b (7) finding. West v. State, supra. The jury’s intent is shown with the requisite clarity. Page v. State, 256 Ga. 191, 194 (345 SE2d 600) (1986).
The defendant further contends the evidence is not sufficient to support the jury’s § b (7) finding. Again, we disagree. The evidence, viewed in the light most favorable to the jury’s verdict, shows a continuing pattern of abuse of the victim by this defendant, culminating in the death of the victim because he was playing with a toy. The defendant chased down and shot his ten-year-old son as the boy begged him not to shoot him. Afterwards, he first dismissed the significance of his act by claiming, “shit happens,” then sought to justify the act first as a lesson in discipline, and than as an act of self-defense. The jury was authorized to conclude that the defendant’s murder of his ten-year-old son was outrageously or wantonly vile, horrible or inhuman, and that it involved mental torture and depravity of mind. Hance v. State, supra; Rivers v. State, 250 Ga. 303 (298 SE2d *7841) (1982).
12. Since the defendant’s conviction on two counts of cruelty to children was supported by the evidence, see Division 7 (b), post, the jury was authorized to consider these offenses in aggravation. OCGA § 17-10-2.
13. The written instructions furnished by the court to the jury were sufficient. Mulligan v. State, 245 Ga. 266 (4) (264 SE2d 204) (1980).
14. The defendant did not object at trial to the state’s attempt to impeach a witness, and the issue raised in his 16th enumeration of error has not been preserved for review. Spencer v. State, 260 Ga. 640 (7) (398 SE2d 179) (1990).
15. Neither did the defendant object to the state’s closing argument. Absent fundamental unfairness, the issues raised in the defendant’s 17th enumeration are not preserved for review. Id.; UAP, § IV (A) (3).
16. The trial court committed no abuse of discretion by denying the defendant’s motion for a mistrial on the grounds of a deadlocked jury when the jury had been deliberating for only three hours. Romine v. State, 256 Ga. 521 (1) (350 SE2d 446) (1986).
17. As noted above, the evidence supports the jury’s § b (7) finding. OCGA § 17-10-35 (c) (2). We do not find that Hall’s death sentence was imposed as the result of passion, prejudice or other arbitrary factor. OCGA § 17-10-35 (c) (1). Hall’s death sentence is neither excessive nor disproportionate to penalties imposed in similar cases, considering both the crime and the defendant. OCGA § 17-10-35 (c) (3). The similar cases listed in the Appendix support the imposition of a death sentence in this case.
Judgment affirmed.
All the Justices concur, except Weltner and Hunt, JJ., who concur specially as to Division 11; Bell, Benham and Fletcher, JJ., who dissent as to Division 11 and the death sentence; Weltner, Benham and Fletcher, JJ., who dissent.as to Division 7 and the conviction on two counts of cruelty to children.Appendix.
Alderman v. State, 254 Ga. 206 (327 SE2d 168) (1985); Conner v. State, 251 Ga. 113 (303 SE2d 266) (1983); Smith v. State, 249 Ga. 228 (290 SE2d 43) (1982); Krier v. State, 249 Ga. 80 (287 SE2d 531) (1982); Cunningham v. State, 248 Ga. 558 (284 SE2d 390) (1981); Brown v. State, 247 Ga. 298 (275 SE2d 52) (1981); High v. State, 247 Ga. 289 (276 SE2d 5) (1981); Strickland v. State, 247 Ga. 219 (275 SE2d 29) (1981); Tyler v. State, 247 Ga. 119 (274 SE2d 549) (1981); Cape v. State, 246 Ga. 520 (272 SE2d 487) (1980); Thomas v. State, 245 Ga. 688 (266 SE2d 499) (1980); Hardy v. State, 245 Ga. 272 (264 *785SE2d 209) (1980); Hamilton v. State, 244 Ga. 145 (259 SE2d 81) (1979); Bowen v. State, 244 Ga. 495 (260 SE2d 855) (1979); Johnson v. State, 242 Ga. 649 (250 SE2d 394) (1978); Alderman v. State, 241 Ga. 496 (246 SE2d 642) (1978); Morgan v. State, 241 Ga. 485 (246 SE2d 198) (1978); Blake v. State, 239 Ga. 292 (236 SE2d 637) (1977); Dix v. State, 238 Ga. 209 (232 SE2d 47) (1977); Harris v. State, 237 Ga. 718 (230 SE2d 1) (1976).