Many times, when a child is born outside of a marriage, it is just a matter of time before the couple end up in Family Court (Probate & Family Court in Massachusetts) to decide issues such as custody, visitation, and child support. More often than not, it is the Mother who has had physical custody throughout the child's life, and is seeking child support from the other parent.
Many non-custodial parents try to avoid paying child support as required under their state guidelines, particularly in Massachusetts, which has among the highest support guidelines in the country (if not the highest). Some think they can make the custodial parent "go away" by threatening to ask for sole physical custody, or shared physical custody. The threats are usually empty, and the custodial parent should not be intimidated by them, as she will almost always prevail absent a history of abuse or neglect of the child.
Unlike a situation following a divorce, - where there is a presumption of shared legal custody, and where physical custody will usually go to the parent who has a history of taking primary care of the child - in an out of wedlock situation in Massachusetts, the birth mother is presumed to have sole physical and legal custody unless a Court subsequently rules otherwise. There is no presumption of joint legal custody, and a non-custodial parent will only be awarded joint legal custody when the parties have shown a history of having been able to work together jointly to further the best interests of the child. In short, a divorced father is presumed to be on equal footing with the mother, while the unmarried father has to demonstrate a history of shared responsibility for the child and the ongoing ability to communicate civilly with the mother regarding the best interests of the child.
Some of the fathers sued for child support have little or no connection with the child since birth, yet they still make this silly threat in the hope that the mother will be scared away. Rest assured: no competent family law judge would suddenly uproot a young child and move their home on the basis of a piece of paper filed by a previously uninvolved parent. The Courts seek stability for infants and children; changes of physical custody only come about by agreement, by marriage, by emergency, or by a history of involvement with the life of the child.
Please note that the Massachusetts Child Support Guidelines presume that the non-custodial parent has the company of the child for up to one-third of the time. Even if the parents share time equally, unless the parents have similar income, the higher-earning parent will probably be ordered to pay something in the nature of child support (albeit at a lower rate!) to equalize the ability of both parents to support the child or children in accordance with their combined joint income.