you shouldn't be sleeping nude till you're old enough to wash your own bedsheets
or
till you're old enough so that your dad won't be temptemted to pull the covers off of you and take a digital picture of you sleeping, posting it on the internet...
I usually sleep in my underwear. But in the summer I like to wear just a T-shirt to bed. I can't get to sleep unless I jackoff before I go to bed. I toss and turn if I don't jackoff.
or
till you're old enough so that your dad won't be temptemted to pull the covers off of you and take a digital picture of you sleeping, posting it on the internet...