Navy Beach in Montauk (navybeach.com, 631-668-6868) will serve a special three-course prix fixe lunch menu. Mothers will receive a complimentary Bloody Mary or mimosa with their meal. The three-course lunch is $48 plus tax and gratuity, and will be served from 11:30 a.m. to 4 p.m. The a la carte menu will also be available.