That's great! The social component was needed in my 3 yr old last year, we started her in preschool and it's made a big change. My 18 mo old is easier, so I'm better than I thought I'd be. I think daycare is both good and bad, and home is both good and bad. We are in the position to have me stay home, so it's hard to argue against. It's tough for sure. Wife wants another, not sure I can handle another. I'm dying to get back to teaching and affecting change. But family first, I'm lucky.
My 4 year old is adding and subtracting very little, and we are on the verge of reading. All kids develop differently, but it's powerful seeing them grow isn't it?