My boss told me this one...
She went round to see some friends in their new house for the first time. Sitting round, having a chinwag, that sort of thing.
Off upstairs to play go her son & their kids. All is well & a convivial evening is being enjoyed by all.

Later, they're saying their goodbyes & my boss's son says to her friend "They don't like you, you know".
"Who doesn't like them?" asks my boss
"The other family that live here" comes the somewhat chilling reply.

Further investigation revealed that while he was upstairs, he'd gone off to the toilet. After a longer than expected absence the other kids had gone to look for him & found him talking to apparently no-one in the main bedroom
(Professor Kenny Martin Hmm? What?, Mon 17 Sep 2012, 17:25, 2 replies)

Kid makes up imaginary friends

(thefuckestuppest cheapened this, on, Tue 18 Sep 2012, 17:15, closed)

Yep, probably. Was still pretty creepy at the time, by all accounts

(Professor Kenny Martin Hmm? What?, Tue 18 Sep 2012, 21:14, closed)