Boy or girl

Two babies were sitting in their cribs, when one baby shouted to the other,’Are you a little girl or a little boy?’
‘I don’t know,’ replied the other baby giggling.
‘What do you mean, you don’t know?’ said the first baby.
‘I mean I don’t know how to tell the difference,’ was the reply.
‘Well, I do,’ said the first baby chuckling, ‘I’ll climb into your crib and find out.’
He carefully maneuvered himself into the other baby’s crib, then quickly disappeared beneath the blankets.
After a couple of minutes, he resurfaced with a big grin on his face.
‘You’re a little girl, and I’m a little boy,’ he said proudly.
‘You’re ever so clever,’ cooed the baby girl, ‘but how can you tell ?’
‘It’s quite easy really,’ replied the baby boy, ‘You’ve got pink socks and I’ve got blue ones.’