Simplify the following text for a Grade 12 native English-speaking person.
Original: After a brief stay in Falls Church , the family moved to Fairfax , Virginia , when James Mello switched from the USGS to a position as assistant director at the Smithsonian Museum of Natural History .
Simplified: After a short time in Falls Church , the family moved to Fairfax , Virginia , when James Mello began work as Assistant Director at the Smithsonian Museum of Natural History .