My husband and I have been separated for six months. We have one child together and one that he has raised since she was three she is now sixteen. He has posed as her father in every aspect. He has signed his name as her father since then. Her biological father is in prison and has been so for fourteen years. Can my husband be ordered to pay support?

he has signed his name as her father since then.
Where?
And the most important additional question-where do you live?
The laws vary from state to state.

What state do you live in?

The short answer is maybe.

What state do you live in?

The short answer is maybe.

Agreed:)
Maybe yes and maybe not;)

Did your husband ever adopt the children? Did he ever sign an acknowledgment of paternity?

And as others pointed out ANY question about law needs to include your general area as laws vary by area.