"Child", an unmarried person under the age of 21.
"Dependent on the court", subject to the jurisdiction of a court competent to make decisions concerning the protection, well-being, care and custody of a child, for findings, orders or referrals to support the health, safety and welfare of a child or to remedy the effects on a child of abuse, neglect, abandonment or similar circumstances; provided, however, that "court" shall include, but not be limited to, the probate and family court and the juvenile court departments of the trial court; and provided further, that when issuing special findings under this section, a court shall be acting under the jurisdiction specified in this definition.
"Similar circumstances", conditions that have an effect on the child comparable to abuse, neglect or abandonment including, but not limited to, the death of a parent.
The health and safety of the child shall be of paramount concern. When considering the child's health and safety, the court shall consider whether present or past living conditions will adversely affect the child's physical, mental or emotional health.
Mass. Gen. Laws ch. 119, § 39M