old Friend

[Jason The Great]

So i just met an old friend... he is one freaking genius and studied in a smart kids high school and going capital for college next year...
He is cool. but i just noticed a little weird thing about him...
he is only child and besides me have no other friends....
he have an imaginary sister named ALICE!!!!!!!! should i be concerned or something for him? Its not normal u know...

[Interstellar]

As weird as it may sound, teenagers that have imaginary friends/siblings are not as uncommon as you would think. He is most likely just using "her" as someone to talk to, someone who is always there to listen to him, because as you said, he is an only child with pretty much no friends. Having "her" allows him to talk to someone who will always agree with him and will never argue with him. As for what you should do, for now I would say just be respectful about the whole thing and definitely don't say anything about "her" that would possibly upset him.

[Let Me Be a Pony]

Lol, have seen weirder shit happening to geniuses, so no.

[Jason The Great]

So it's no big deal then, still kind of creep me out....

[Let Me Be a Pony]

So it's no big deal then, still kind of creep me out....

My guess is that he's been watching too much "Foster's Home for Imaginary Friends".