(a) Unless otherwise resolved by agreement of the parents under section 9-201, the court shall allocate responsibility for making significant life decisions on behalf of the child, including the child's education and health care, to one parent or to two parents jointly, in accordance with the child's best interest, in light of:

(1) The allocation of custodial responsibility under section 9-206 of this article;

(2) The level of each parent's participation in past decision-making on behalf of the child;

(3) The wishes of the parents;

(4) The level of ability and cooperation the parents have demonstrated in decision-making on behalf of the child;

(5) Prior agreements of the parties; and

(6) The existence of any limiting factors, as set forth in section 9-209 of this article.

(b) If each of the child's legal parents has been exercising a reasonable share of parenting functions for the child, the court shall presume that an allocation of decision-making responsibility to both parents jointly is in the child's best interests. The presumption is overcome if there is a history of domestic abuse, or by a showing that joint allocation of decision-making responsibility is not in the child's best interest.

(c) Unless otherwise provided or agreed by the parents, each parent who is exercising custodial responsibility shall be given sole responsibility for day-to-day decisions for the child, while the child is in that parent's care and control, including emergency decisions affecting the health and safety of the child.