Sorry to add on..
<extract from ICA website> cos i can't seem to paste the link..
If the minor's parents are divorced, and one parent is currently residing overseas, must the consent of both parents be obtained before a name change can be executed?
Yes. The child's name is an important symbol of his identity and his relationship with his parents. Hence, the consent of both parents must be sought before the child's name can be changed. However, if the parent residing overseas cannot be contacted despite reasonable efforts, the parent who executed the deed poll will be required to make a declaration that the other parent is not contactable.
So I guess, if you file a police report or something before that father not around... then.. it should work ba?