Lyrics for the "I saw Mommy kissing Santa Claus" Christmas Song or Carol

I saw Mommy kissing Santa Claus
Underneath the mistletoe last night
She didn't see me creep
down the stairs to have a peep
She thought that I was tucked
up in my bedroom fast asleep
Then
I saw Mommy tickle Santa Claus
Underneath his beard so snowy white
Oh
what a laugh it would have been
If Daddy had only seen
Mommy kissing Santa Claus last night