Following VenetianPrincess's revelations on the origin of her YouTube channel name, MuggleSam confirms what you might have guessed about hers:
"I am a huge Harry Potter fan so when I was trying to come up with a YouTube username in 2006, I had Harry Potter on the brain. I came up with MuggleSam. In the Harry Potter books a muggle is a person without any magical powers. Basically a normal human. And Sam is short for my name Samantha. I then handed my daughter a Harry Potter doll and that was the inspiration for our very first YouTube video."