How old is too old for a sleepover? When it’s a grown-up sleepover with alcohol, party tunes and all kinds of misbehaviour, the upper age limit would appear to be pretty high. Just because a bunch of so-called adults will be in attendance doesn’t mean this is going to be a po-faced grown-up affair. Far from it: a secret location, onesies, teddies and pillow fights are the order of the day. Can you handle the suspense? Over 21s only. Dresscode: pyjamas, onesies, robes and teddies. We can't tell you the exact location yet, but we can tell you the event venue is in Camberwell, London Zone 2.