Delilah Belle Hamlin looks stunning in a black string bikini

Amelia Gray Hamlin bares her toned midriff in a cropped white tank while out in Manhattan

Amelia Hamlin rocks a nearly all-workwear outfit while stepping out for a stroll in New York City

Amelia Gray Hamlin and Brooke Shields attend Funny Or Die and PEOPLE's Washington's Funniest Party