My Nephew did it, but I think he was a bit older maybe 16. He had to go to court to do it as well and he had to state why he wanted his name changed. I don't know the finer details like costs etc. But he did get his request approved. He was in same position dad walked out when he was 2 and wanted nothing to do with him. He is an only child so didn't have the sibling scenario to present either.