Changing a Paternal Name in Mississippi

My question involves name change laws in the State of: Mississippi

Hello, my question is where to start, my granddaughter was born last year and at the time we all knew; my daughter and the two gentlemen involved with her that she wasn't sure which of them was the father. One of them signed the birth certificate. Since then it has become apparent to all parties that the other gentlemen is the biological father - all parties involved wish to have her birth certificate changed to reflect her biological father and have her name changed; what do we do, where do we start??

Bio dad can commence a paternity action, and request DNA testing. If the DNA testing establishes his paternity, and nobody objects, the court should name bio dad as the legal father and order the birth certificate corrected.