The Simpsons (Lisa's first word)
I saw Bambi for the first time yesterday and spotted that Bambi's delivery when he's repeating the word "bird" is just like Lisa repeating "Bart" as her first word.
It's hard to think it's a coincidence, given the way The Simpsons has a habit of this kind of referencing but I'm surprised it's not mentioned anywhere else (unless I've missed it in my searches).