This is a sticky sort of situation. Legally, your husband is only required to provide for his biological children or any he legally adopts. You can try to pass off your husband as the biological father (but he could figure it out, sue for a paternity test, find out he's not the father, and therefore not have to care for the child). You can confess to your husband and if the biological father is willing to give up his legal rights (and therefore responsibility to support the child) your husband can adopt the child.
I Had A Baby By Another Man While I Was Still Married. Is The Man Still Responsible To Take Care Of His Child? Or Is The Current Husband?
My Ex Girlfriend Had Two Kids By Me While She Was Still Married. Is The Husband Still Responsible To Take Care Of My Children? Or Is I'm Still Obligated To According To New York Law?
The other man (not husband)
Yes he is still responsible to take care of his child. If the current husband adopts the baby with the father consent then he will be responsible.
The currant husband if you listed him as the father on the birth certificate and or hes been looking after the child and supporting that child