My kid expenses:
Daycare (until they get into school age 5ish): Averaged out to around $250 per week * 52 weeks (had to pay even if kid didn't go to keep our spot) * 3 kids * 4.5 years = $175,500.
Summer Care (wife is SAHM now so these were cut shorter): $250 per week * 16 weeks * (5 years for oldest, 3 years for middle kid, 1 year for youngest; 9 years) = $36,000
Difference in health care: $340/month vs. (29 + 34 - not adding the 34 due to wife going SAHM, but chioces were single and family) = $277 per month * 11 years so far, will be at least 17 if all kids are off health care by age 18: $59,832
Kid Activities: Swim lessons, piano lessons, soccer, football, dance, entertainment etc: about $345 a month ($115 each kid, 1st - 12th grade). Started around the time youngest hit 1st grade, still going, so assume college it ends: $45,540
Assumed College Expenses: 100k each: $300k
Total for all three kids will be something like $616,872 not counting food/clothing, or $205,624 each. I'm not claiming to be frugal with our kid expenses. We spend a lot on experiential things like music and sports, but not much on clothing brands etc.