Joint consent is required for Changing Child's Surname Section 4 of the Family Law Act (Cth) 1975 considers changing a child’s surname to be a major long-term issue in relation to the care, welfare, and development of a child. In Queensland, a child’s surname can only be changed with the consent of both parents listed on the child’s birth certificate. If there is consent by both parents, a joint application to the Registry of Births, Deaths and Marriages can be...