Harry Potter and Mary Poppins
I think that Harry Potter is actually ripping off Mary Poppins.
First of all, Harry rhymes with Mary.
Second, their last name have "po", and the rest only have a four letter difference:
P q r s T
E f g h I
N o p q R
What's left is the s...
and the theme song of Harry Potter mixes well with "Chim Chim Cheree" (154kb, WAV)