Even though most kids start doing some talking in the first couple of years of life, language is something that they continue to learn over time. It's pretty cute, actually. All of the silly things kids say, I mean. They are figuring out sentence structure, adding vocabulary all.the.time. Just learning what works. I imagine it's fairly common for little kids to get mixed up about many things in the English language. Oh sure, punkin is an acceptable substitute for pumpkin. Pronunciation differences are cute. But changing a person's personal pronoun can be a tad embarrassing!
When Duncan was four or five, he started tagging all people with male personal pronouns. For example, "There's Mommy! What's he doing? Playing his flute?" And I say, "Um, Duncan? I'm a girl. 'There's Mommy. What's she doing?'" He did this for a long time. He gets it right now, but sometimes he inserts that italicized she to make sure we know he's making that extra effort and emphasis.
Miranda really likes to mix things up. Instead of referring to everything as a male, she does tend to lean towards using the feminine. We've tried the same repetition with her that worked so well with Duncan. Miranda will say, "Grandpa has her hat on!" And we respond, "Grandpa has his hat on." Miranda likes to keep us on our toes, though. Just tonight Duncan was having a pain in his eyes. Miranda was very concerned. She said, "Is Duncan ok? Did he get something in her eyes?!" That Miranda! Always has to do things her way!