Mass. Gen. Laws ch. 209 § 37
If the parents of minor children live apart from each other, not being divorced, the probate court for the county in which said minors or any of them are residents or inhabitants, upon complaint of either parent, or of a next friend in behalf of the children after notice to both parents, shall have the same power to make judgments relative to their care, custody, education and maintenance, and to revise and alter such judgments or make new judgments. In determining the amount of the child support obligation or in approving the agreement of the parties, the court shall apply the child support guidelines promulgated by the chief justice of the trial court, and there shall be a rebuttable presumption that the amount of the order which would result from the application of the guidelines is the appropriate amount of child support to be ordered. If, after taking into consideration the best interests of the child, the court determines that a party has overcome such presumption, the court shall make specific written findings indicating the amount of the order that would result from application of the guidelines; that the guidelines amount would be unjust or inappropriate under the circumstances; the specific facts of the case which justify departure from the guidelines; and that such departure is consistent with the best interests of the child. In furtherance of the public policy that dependent children shall be maintained as completely as possible from the resources of their parents and upon a complaint filed after a judgment of support, orders of maintenance and for support of minor children shall be modified if there is an inconsistency between the amount of the existing order and the amount that would result from application of the child support guidelines promulgated by the chief justice of the trial court or if there is a need to provide for the health care coverage of the child. A modification to provide for the health care coverage of the child shall be entered whether or not a modification in the amount of child support is necessary. There shall be a rebuttable presumption that the amount of the order which would result from the application of the guidelines is the appropriate amount of child support to be ordered. If, after taking into consideration the best interests of the child, the court determines that a party has overcome the presumption, the court shall make specific written findings indicating the amount of the order that would result from application of the guidelines; that the guidelines amount would be unjust or inappropriate under the circumstances; the specific facts of the case which justify departure from the guidelines; and that such departure is consistent with the best interests of the child. The order shall be modified accordingly unless the inconsistency between the amount of the existing order and the amount of the order that would result from application of the guidelines is due to the fact that the amount of the existing order resulted from a rebuttal of the guidelines and that there has been no change in the circumstances which resulted in such rebuttal; provided, however, that even if the specific facts that justified departure from the guidelines upon entry of the original order remain in effect, the order shall be modified in accordance with the guidelines unless the court finds that the guidelines amount would be unjust or inappropriate under the circumstances and that the existing order is consistent with the best interests of the child. A modification of child support may enter notwithstanding an agreement of the parents that has independent legal significance. If the IV-D agency is responsible for enforcing the case, an order may also be modified in accordance with the procedures set out in section 3B of chapter 119A. The probate court may make appropriate orders of maintenance, support and education of any child who has attained age eighteen but who has not attained age twenty-one and who is domiciled in the home of a parent, and is principally dependent upon said parent for maintenance. The court may make appropriate orders of maintenance, support and education for any child who has attained age twenty-one but who has not attained age twenty-three if such child is domiciled in the home of a parent, and is principally dependent upon said parent for maintenance due to the enrollment of such child in an educational program, excluding educational costs beyond an undergraduate degree.
If the court makes an order for support or maintenance on behalf of a child, the court shall require either parent to provide health care coverage for the child if such coverage is available at reasonable cost and accessible to the child. The court may require the obligor to pay an amount toward the obligee's cost of health care coverage or toward uninsured medical expenses on behalf of the child. If the court determines that an order for health care coverage is not in the best interest of the child or creates an undue hardship for either parent, the court shall enter written findings.
If the child is enrolled in MassHealth, an equivalent program in another state pursuant to 42 U.S.C. 1397aa et seq. or 42 U.S.C. 1396a et seq. or an equivalent program in another state that is substantially similar to the program established in chapter 118E, the court shall order the obligee to maintain coverage as long as the child remains eligible; provided, however, that the court may also order the obligor to enroll the child in private health insurance if:
If the IV-D agency under chapter 119A is responsible for enforcing the order, the court shall order the parents to notify the IV-D agency of any changes in the availability and terms of health care coverage. For the purposes of this section:
When a court makes an order for maintenance or support, the court shall determine whether the obligor under such order is responsible for the maintenance or support for any other children of the obligor, even if a court order for such maintenance or support does not exist, or for any preexisting order for the maintenance or support of any other children from a previous marriage, or for any preexisting order for the maintenance or support of any other children born out of wedlock. If the court determines that such responsibility does, in fact, exist and that such obligor is fulfilling such responsibility such court shall take into consideration such responsibility in setting the amount to be paid under the current order for maintenance or support.
No court shall make an order providing visitation rights to a parent who has been convicted of murder in the first degree of the other parent of the child who is the subject of the order, unless such child is of suitable age to signify his assent and assents to such order; provided, further, that until such order is issued, no person shall visit, with the child present, a parent who has been convicted of murder in the first degree of the other parent of the child without the consent of the child's custodian or legal guardian.
Mass. Gen. Laws ch. 209, § 37