[dvtv75]

> My younger daughter is reading and writing simple words a full year before Kindergarten, thanks to engaging educational apps.

So was I. I was reading books to my parents and grandparents by the time I was three years old. By 8 years old, I had the reading age of an adult, and when my father eventually regained legal access to us (edit: when I was 9 years old), I was correcting his spelling, pronunciation, and grammar.

My entire family thought I was some kind of genius, but it turned out that I have a moderate-to-severe learning disability, and this was an early symptom of it.

I'm not trying to diagnose your daughter, don't even imagine that. However, I am suggesting that there may be other reasons for your daughter's apparent advancement.