As the parent of a four-year-old girl, I can confirm that it's pretty incredible to see how much information they're able to retain. My kid remembers every gift she's ever received and who gave it to her, often stumping me because I barely remember what we ate for dinner last night. That's why I'm not surprised to see how much four-year-old Mia Grace knows about Marvel superheroes since the girl probably soaks up every little thing her geeky dad tells her about Iron Man, Thor, the Avengers and various comic storylines.
Watch as her father quizzes her while the family is out for a drive, and don't feel bad when you realize she knows way more about superheroes than you do. Her brain is a sponge, and yours is currently busy trying to remember the name of just one character on Game of Thrones.
Just one. C'mon, you can do it!