live next door (to one)
To live in a house, apartment, building, etc., that is immediately adjacent to one. There has been a family living next door to us for over a year, and we still have yet to meet them. My best friend lived next door until we both started high school, when she moved to a different part of the state.
live next door (to someone)
to live in the house or dwelling next to someone. I live next door to John. John lives next door to me. John lives next door.