Born by C-section Wednesday afternoon at UCLA Hospital, he weighed 6 pounds, 11 ounces, "Access Hollywood" reports. The pop star known for her scanty outfits has a "very small and very low scar," a source said.
Spears' fifth floor room with a tented balcony costs $3,000 a night and her family and security have an additional seven rooms for a grand total of $20,000 per night, the source told the TV tabloid show.
The new mom isn't eating the usual hospital fare -- she has a private chef in a kitchen adjacent to her hospital suite.
Sean is the first child for Spears, 23, and Federline, 27, who has two young children with his ex-girlfriend, Shar Jackson.