Ned has a cold, and Newton shrinks himself down so he can enter Ned's body and cure him.

When Newton overhears Ned rehearsing his lines as a ring bearer at a family member's wedding, he mistakenly thinks Ned is going to marry someone other than Linda. He takes it upon his own to ruin the wedding, not knowing that it's not Ned who's getting married.

Ned has lost a tooth, and left it under his pillow for the Tooth Fairy. When the fairy comes, though, Newton thinks he's a burglar and attacks him. This results in the Tooth Fairy cursing Ned to have giant teeth, and Ned can only have the curse lifted if he does several tasks for the Fairy, such as counting all the newts in the world and doing his laundry.