No children vs. 2 children and how it affects fire

I posted a few days ago about owning vs renting and thought I'd also look at having kids. Here's the chart.

Assumptions:

• Homeowner, 600k mortgage, paying it off in 16 years
• 930k investable assets
• current combined income 240k gross
• Couple, age 33/34
• Post-retirement, no mortgage, non-kid expenses are 79k/yr in today's dollars (includes 18k/yr marketplace health insurance, 15k/yr home repair/tax/insurance + 3800/mo in other expenses)
• kid expenses include Montessori school until age 5 50k/yr, age 6-12 10k/yr, 13-17 12k/yr, 4 year private college (cost increases CPI + 2%)