Today she was looking at a book that had some tally marks - thirteen, actually. So I told her it was a way of counting or writing a number. You know how tally marks look - the number 13 had two sets of 5 and one set of 3. So I asked her (really just out of curiosity because she often surprises me) "what is five plus five?" and she said "ten!" Then I asked "what is ten plus three?" and she said "thirteen!" Yeah, that was a serious WTF moment.
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She is only 17 months as of today
I agree, WTF is a reasonable response! I assume from what you say that she was answering these particular questions in the presence of a tallied 13 written down where she could see it, which slightly reduces the WTF quotient, but not much!
As you say, you really don't know what she'll be like when she's 5, and especially, you need to avoid the presumption that she'll necessarily have more extreme educational needs than your DS. Depending on how much he talks to her about numbers it could well be that what you're seeing in her tells you at least as much about him as about her! But yeah, it's sensible to assume that you're going to need something special in a school. There are PG children happy in schools, so don't give up. That's a very hopeful conversation you had the other day - exactly what you want is a school where the staff will pay attention to what each child needs educationally and work out how to provide it without you needing to force them. Such schools do exist!
