A legal definition of 'sleepover' is as follows:
-One or more people stay over your house
-With the intention of staying there for the entire night because it would be IMPRACTICAL for them to go home
-Activities are undertaken at the house that you are staying at
-Being at the persons house is the main focus point of your night
-It is NOT a sleep over if you live out of home
-A girl/guy staying over for the purpose of a relationship of some kind is NOT a sleepover, it is sex/a relationship.
Impractical in the situation is defined as: There is going to be stuff done until the evening hours in which it would be stupid for someone to come and get you or to leave yourself, especially on your own.
Sleepovers were so much fun as a kid.