Jingle Bells

Right now I am in my room. Melissa is on the potty taking care of business. She's also serenading all who care to listen to her version of Jingle Bells. Where she doesn't know the words she substitutes "la la la all the way." Not only that, but she's in tune and she's pretty good! I didn't even know that she knew Jingle Bells! I wonder where she picked it up?