Does a cat realize that a large kitten is still a kitten?

My friend recently got a male mainecoon kitten who is now 16 weeks. He’s already bigger than her resident female cat who’s about 2 years old.

My question is, even though the mainecoon kitten is larger than her (the resident cat), does she still realize he’s a kitten? Or does she think he’s just a really childish adult cat?