People keep asking me, is the baby doing this or that yet? So and so is doing this or that already. I don't worry about it too much though, how many 30-year olds do you see wearing diapers and sucking on pacis? If he turns 15 and can't sit up or roll over, there  might be an issue. Other than that, they will do it in their own time, and if you can find me a toddler who can do their parents' taxes, I'll be sufficiantly impressed.