I remember when I realized ds knew them - he had no language at 18 months, started ST at 20 months, and at 22 months, just for fun, I pointed out all of the upper and lower case letters on the fridge (again, leapfrog). He knew them all! Of course, then I started freaking out thinking he was autistic. Turns out he just loved the DVD!

Despite the experiences of the previous posters, I don't believe "well before age 3" is the norm.
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