We granted the natural mother’s application for discretionary appeal from the trial court’s denial of her motion for new trial in the father’s change of custody action. In that action, the court granted joint legal and physical custody of their nine-year-old son to each of the parents and provided that physical custody would alternate each July 1. The father had been awarded visitation rights at a hearing in the mother’s previously filed paternity action. The mother resides in Colbert, Georgia, and the father resides in Statesville, North Carolina.
The child lived with his father for over two years during kindergarten, first grade and the beginning of his second-grade year. He has lived with his mother at all other times. When the child was returned to his mother in 1993, he was having emotional and educational problems, did not know his A, B, C’s, and could not count to 20. His mother enrolled him in a special education class in 1994 and he made the merit list for the first time. He made five A’s and two B’s. His special education teacher testified that he had shown significant improvement.
1. In her first enumeration of error, the mother contends the trial court improperly granted joint legal custody because neither party requested it. The trial court, however, is required to consider joint custody whenever it finds both parents fit and equally capable of caring for their child. Although the trial court is not required to grant joint custody, it may do so whenever it finds joint custody is in the best interest of the child. Baldwin v. Baldwin, 265 Ga. 465 (458 SE2d 126) (1995). As the trial court found this arrangement to be in the child’s best interest, it was not error to award joint custody just because neither party requested it.
2. The mother also argues that insufficient evidence was presented to warrant the change from sole custody to joint custody, as no material change in circumstances was shown. However, because a party may not expand her enumeration of error by arguments and citation in the brief, we do not consider her arguments on this issue. In the Interest of S. K. L., 199 Ga. App. 731, 734 (2) (405 SE2d 903) (1991).
3. The mother further argues that the terms of the change of custody order are detrimental to the child. The court’s order transfers custody of the child between the parents on July 1 of each year until he reaches the age of majority. This order has the effect of requiring the child to change schools, make new friends, and change activities every year. It would also require an annual change in the child’s mental therapy and counselor and cause a disruption of his special *36education program. However, the trial court, in its order, mandated that the child continue to participate in each of these programs.
No evidence shows this arrangement will serve the child’s best interest. On the contrary, evidence from teachers and mental health professionals shows this child suffers from attention deficit disorder and depression, and that he requires special education. A psychologist testified that the child’s condition requires him to remain in a stable environment and opined that the yearly transition would adversely affect the child. Dr. Glazer, who performed psychological evaluations on the parents and the child, testified that he did not “see any evidence that [the mother and father] could share decision making at the present.” He also testified that “in our work with the child [the change of custody order] is probably the worse scenario that I can imagine in that with the problems that he’s seeing mental health people for and help from the school for, stability and consistency are the most important things. And the order calls for him to be moved about all the time. And I’m very concerned about that.”
In Lifsey v. Lifsey, 256 Ga. 613, 614 (2) (351 SE2d 637) (1987), the Supreme Court struck down a nearly identical custody order. If there is any reasonable evidence to support the trial court’s decision as to what is in the best interest of the child in a change of custody action between parents, such decision will be affirmed on appeal. Lifsey, supra. Here, the trial court recited certain negative conclusions, concerning each of the parents. It concluded that the mother’s relationship with Earl Hardy was detrimental to the child. It further concluded that the mother’s allowance of a trip to Florida by the family, including the son and Earl Hardy, when the court had ordered her to not allow the child to be around Hardy, constitutes a material change that is detrimental to the child. There is no evidence in the record that there was any inappropriate conduct engaged in between the parties and the mother’s daughter was also present.
The court concluded that the father had recovered from a onetime drinking problem. The father had previously been held in contempt of court for failure to pay child support and was in arrears in the amount of $8,175 in 1994. The father reported an adjusted gross income on his federal income tax return for 1994 in the amount of $61,341. The trial court, however, awarded joint legal and physical custody of the child to each of the parents, thereby establishing that each of the parents was fit and capable of having custody of said child.
Here, as in Lifsey, supra, there is no evidence in the record that might support a finding that the best interest of the child will be served by requiring that he change residence, school system, special education teachers, doctors, therapists, circle of friends, activities, and states on a yearly basis. For that reason, we reverse the trial *37court’s order regarding the particulars of the joint custody arrangement and remand this matter for further consideration as to this issue, consistent with this opinion. Pursuant to OCGA § 19-9-3 (a) (2), the trial court should “exercise its discretion to look to and determine solely what is for the best interest of the child . . . and what will best promote [his] welfare and happiness and . . . make its award accordingly.”
Judgment affirmed in part, reversed in part, and case remanded.
McMurray, P. J., Pope, P. J., and Johnson, J., concur. Andrews, C. J., Smith and Ruffin, JJ, and Senior Appellate Judge Harold R. Banke concur fully and specially. Beasley, J., concurs in part and dissents in part.