Gender assumption based on sex role stereotypes of a three-year-old watching My Little Pony: Friendship is Magic

The title's a bit of a mouthful so I'll get right to the point: Natalie thinks that two of the six star Ponies in this show are dudes.

We're past the phase where she uses the wrong personal pronoun by mistake. She definitely understands genders. But no matter how often I remind her that all her ponies are girls, in her mind they are male, and she quietly insists on referring to them as such.

Pop quiz for anyone who watches the show! Which two are the boys? Write down your answer and then turn to the back of the book. Here are the "mane" characters (see what I did there?), their defining characteristics (from descriptions at Hasbro.com), and Natalie's gender assessment.

• Twilight Sparkle: dutiful and intelligent (female)
• Applejack: dependable and hard-working (male)
• Fluttershy: timid and caring (female)
• Rainbow Dash: capable and athletic (male)
• Pinkie Pie: playful and fun (female)
• Rarity: beautiful and talented (female)

I don't have any deep analysis on this observation. It was just surprising to me that such a young kid would make this type of judgment based on (as far as I can tell) personalities and behavior that are traditionally considered masculine. The show itself is deeply feminist and I'm glad there are so many truly unique characters Natalie can relate to... so maybe it doesn't matter whether she thinks they're male or female.

OK, I lied. I did overthink it. I'd love to hear your opinion.