Once you have a child custody agreement, you have restricted options for getting it changed. Furthermore, a custody change is unlikely to be granted if it does not seem to be in the best interests of the child.
That said, there is still a lot of room to negotiate for custody changes within these boundaries. Here are some common scenarios when custody may be modified:
One parent voluntarily gives up some custody/all custody
One scenario is when one of the parents, for whatever reason(s), decides to give up custody rights. For example, this could happen if the parent realizes that he or she is unfit or is unable to effectively parent the child.
Alternatively, if the parent places the child in another person's care for at least six months, that may warrant a custody change except in cases of military service.
The child initiates the process or prefers the change
A child who is at least 12 years old should typically have a lot of say in custody arrangements under Texas law. Of course, the child does not have the final say, but if he or she wants a custody change, the courts take that preference seriously.
The bottom line remains whether the modification is in the child's best interests. So, a proposed custody change for a child who wants Parent A to have sole custody because this parent has no rules in the house might not be in the child's best interest.
One parent's or both parents' situations have changed significantly
Parents' lives can change for many reasons, including criminal convictions and jail time, a relocation or health concerns. The changes do not necessarily have to be negative. For example, a parent who struggled with addiction and who was granted limited visitation because of that could decide to petition for expanded access to the child after being provably sober for a few years.