My kids are all different. And exposure to adults and reading has been different. But two cracked the code, one learned from instruction in school, and one is on her way. I see her sounding out, and I see she has memorized words and signs and such.
By the way, and this will make you smile, I have learned not to chatter in the car. When I drive my mom, who has Alzheimers, around, she doesnt have much frontal lobe / executive functioning, so she chatters on and on about superficial things she sees like peoples tail lights or wheels. Or the colors of the cars around us. Endlessly. Many times I want to slam into the center divider or off a cliff. I actually called my ex and my brother and apologized to them for any and all car chattering I ever did. CURED. It is the absolute worst!
No Smile there, but to each his own.