Washington, Nov 26 : Britney Spears is amazed by her two sons’ ghostly imaginations as they think her house is surrounded by monsters and thus make her search all over the mansion for ghosts.

The ‘Toxic’ star has admitted she''s amazed by Sean Preston and Jayden James'' imaginations, but said that its impossible to put them to sleep until she''s made sure there are no ghoulies lurking in the garden.

"They''re obsessed with monsters, and every night we look outside, and we have to show them that there''s no monsters out there: ''It''s dark outside, but there''s nothin'' out there,''" Contactmusic quoted Britney as telling Rolling Stone magazine.

Meanwhile, the pop sensation also said that she still can''t believe she''s mum to two tearaway kids.

"They''re going to pre-school now... and seeing them in their little classroom and seeing Jayden being bad or not listening? It''s like, those are mine, and it''s just crazy,” she said.

Under the terms of her custody agreement with ex-husband Kevin Federline, Spears sees her kids three days a week with one overnight stay. (ANI)