I live in Florida. I have joint custody of my 10 year old son. My son does not like his father. He really doesn't know him very well. It's really a long story but he says his daddy is my new husband. Well not really "new", we've been together since my son was 2 years and 8 months old. This is the only man he remembers growing up -- to him thats daddy. His father did'nt start coming around until he was a little older on a regular basis. My son has been complaining A LOT lately about his last name being different than everyone else in the home (my husband has custody of his 15 year old son). He has been complaining since first starting pre-school(4 years old). We have a dog and at the vet she is listed under his last name , and that has worked for the last couple of years. But he's VERY smart and has caught on that the dog doesn't count. He wants our last name --not his fathers, he wants his daddys name. No,-- I have not asked my ex, I just know he would say no. He owes $40,000 in back childsupport and the "on-going" he has to pay. He also has another kid he pays child support on. Anyway-- the question I need to know is, do I need his consent to legally hyphenate the childs name. I would hyphenate it for legal and medical papers, but for everyday use and school he would drop his fathers last name and just use his daddys. Sounds like a great plan. Can I do it? It would really make my little boy happy!!!