Third MMR dose

Necessary bang bigyan si baby ng 3rd MMR dose? May 2 doses na anak ko, 9 months and 12 months. Ngayon, he's 16 months old, turning 17. Yung local health center nag sabi na bigyan daw ng 3rd dose. Pero wala naman ito sa baby book. Tinanong ko dalawang pedia namin. Yung isa sabi nya ok lang daw yun as booster. Yung isa naman, sabi nya ok na daw yung 2 doses. Kayo ba, ilang doses ng MMR si baby? #advicepls #firstbaby