I have to agree with what everybody else has said. What the child calls each person is not near as important as the relationship between the two.

When I work in the public school I allow the kids to call me by my first name. I introduce myself with my first name to the children regardless of how old they are. A school administrator asked in a semi-accusatory manner why I did not make the kids address me as Mr. and by my last name, as a sign of respect; I told her respect is much more than a name or word. My presence and behavior command respect, not my title. Just as how Daddy ‘T’ and Daddy ‘J’ behave around the child will have much more effect on what the kid and the general public perceive their relationship to be. If Daddy ‘T’ acts like a responsible adult and sets consistent rules and limits for boy, but is also there for the him when is he hurt, scared, or sad, he may earn the title father. If Daddy ‘T’ just try’s to be the youngsters friend and he will never be regarded by the boy as his “dad,” even if that is what he calls him.