Another answer is to both also dun save, or see who's nearer, save who first.
Some people also will say wife wil be with you but mother wil die very soon. So save wife first.
I prefer girls than boys, some son listen everything to wife, abandon parents, or some son listen everything to mother, neglect wife.
Girls mostly more understanding and won't create as much trouble as son. This is from those I knowla. No obligation.
Think the lifeguard's answer is save the person that goes under 1st, cos a struggling person will pull you down as well... hahaha... then when the other stop struggling... can save both... hahaha...
I'm expecting my first daughter in Aug.