We recently had a vacation at the Stilts Beach Resort in Calatagan Batangas. The place is very quiet and family friendly. I have an 11 month old baby and he had a blast. The sand is baby friendly and the water is very calm. He enjoyed the pool too. Your wife could relax in the warm water of the ocean while your 3 year old build castles. Check it out!
Hamilo coast, Pico De Loro. Very family friendly! :)