“I live in the state of Florida. I’m married with four beautiful children. I had a one night stand with another woman. A month later she told me was pregnant. I had a paternity test done and found out that I’m the child’s father. I’m sending money for the child. By the state of Florida am I required to sign the birth certificate even though its carrying my last name.”

You are not required to sign the birth certificate. The DNA test is enough to prove you are the father. If there’s any way you can do right by that child, please do.