See you later, alligator!

'See you later, alligator!' is something parents and grandparents say to little kids. The response from the child is, "After while, crocodile!"

Example:
-See you later, alligator!
-After while, crocodile!

To hog

'To hog' means to keep something all to yourself, so that nobody else can have any or use it. It's a common expression that kids use.

Example:
-Mom, she's hogging the computer again!
-Okay, you have 5 more minutes and then it's your sister's turn.