Lambert Family of Plattsburgh, NY /Previously of W. NY, NJ<

My husband's family name is Lambert. I have search back to his grandfather. The search has lead us to West New York, NJ. His grandfather, Leroy M. Lambert, moved from New Jersey to Plattsburgh, NY. Leroy's father's name was (who is my husband's great grandfather) Frank X. Lambert and his mother's name was Mary Ellen Mac-Atavey. I am trying to find out where they died and what year so I can go to the next level.