Starfleet brat was an informal term for a child raised by a parent or parents serving in Starfleet.

Geordi La Forge, the son of two Starfleet officers, described himself as a Starfleet brat. (TNG novel: Greater Than the Sum)

The term is a play on the real-world term "military brat". It was also used on-screen in the VOY episode "In the Flesh.