An Act relative to determining the best interest of children in probate and family court

This bill updates Massachusetts law to provide clearer definitions for how parents share decision-making and living arrangements for their children in family and probate court. It establishes specific terms for shared versus sole responsibility regarding major decisions like education and medical care, as well as shared versus primary residential time. The legislation requires courts to consider the child's welfare when dividing parental duties and mandates that parents submit a detailed parenting plan during contested cases. Additionally, it clarifies that temporary shared legal custody applies automatically when a case is filed, unless there is evidence of abuse or neglect.