My sister adoped my child , but my ex husband in prison never sighned the papers . Can I get him back if my life is together?

How did you manage to get away with the adoption in the first place, if your ex never signed the papers?

How old is the child? How long ago was the adoption?

If the answer to EITHER is more than 6 months... your odds are close to zero.

It should have been explained to you at the time you signed that adoption is FOREVER, not just until when you get your life together.

It is probable the court terminated his rights because of his criminal record without requiring his signature.

Why did you sign?