The popstar became a father for the first time last month when wife Ayda Field gave birth to their daughter, nicknamed Teddy. Williams told Style magazine that he is impressed by the way public school pupils behave.
"I think aristo kids are well grounded, they're smart and naughty and have original thoughts," Williams said. "I don't meet many aristo kids who aren't well mannered."
The singer also joked that "Hogwarts is up the road", referring to the exclusive Marlborough College where Catherine, Duchess of Cambridge and her sister Pippa Middleton were educated.
Williams also revealed that Theodora's birth had taught him "a huge lesson in selflessness".
"That's the thing I'm scared about, because I've been a pop star since I was 16," he said. "I haven't had to wipe my arse since I was 16, and now I literally have to wipe someone else's."
Williams has previously said that he will take his daughter on tour with him in 2013.
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