Which term refers to a situation where parents share in the decisions about major aspects of a child's life?

The situation in which parents share in the decisions about major aspects of a child's life is correctly referred to as joint legal custody. This term highlights the legal arrangement where both parents have the authority to make significant decisions regarding the child's upbringing, such as education, healthcare, and religious upbringing. Joint legal custody emphasizes the shared responsibility and collaboration between the parents in guiding the child's development and welfare.

In contrast, sole custody refers to a situation where only one parent has the legal authority to make decisions for the child, limiting the other parent’s involvement in those critical areas. Joint physical custody, on the other hand, focuses on the living arrangements and time-sharing of the child between both parents, rather than decision-making authority. Lastly, third-party custody involves someone who is not the biological or legal parent taking custody, which is unrelated to the decision-making dynamics between the parents themselves. Therefore, understanding the nuances of these terms is crucial in family law, particularly when assessing the roles and responsibilities of parents post-separation or divorce.