孩子稱姓，並非固定不變，法律允許在家庭發生一定變故後，子女改從他方父母之稱姓。
民法第1059條第4項得改從另一方父母稱姓之情形，分別是「父母離婚」、「父母之一方或雙方死亡」、「父母之一方或雙方生死不明滿三年」以及「父母之一方顯有未盡保護或教養義務之情事」等。只要發生前開情形，法院即得「依父母之一方或子女之聲請，依子女之利益，變更子女之姓氏。」
因此，如果離婚後，夫妻之一方取得原從他方稱姓之子女之監護權，可依前開規定聲請法院裁定變更子女之姓氏。
A Child’s surname is not permanently fixed. When certain family circumstances change, the law allows the child to change their surname and take that of the other parent.
According to Article 1059, Paragraph 4 of the Civil Code:
(1) Where the parents divorce;
(2) Where one or both of parents are deceased;
(3) Where one or both of parents’ lives have been uncertain for three years; or
(4) One of parents has obviously not fulfilled his/her obligation of care-giving.
In any of the following aforementioned circumstances occur, the court may, upon the request of one parent or child, order a change of the child’s surname, based on the best interests of the child.
Therefore, if one parent obtains custody of the child after divorce, and the child originally bears the other parent’s surname, that parent may apply to the court to have the child’s surname changed in accordance with the above legal provision.