Career opportunity but would require 50+ hour weeks

Got offered a promotion that's basically a dream role. The money would be great and it looks incredible on a resume. Problem is it's a startup role and they want commitment. I have two kids under 5 and I'm finally in a place where I'm doing school pickup and evening routines with them. If I take this I basically become a check in the mail to my family. Wife says it's my call but I can see the worry on her face. This shouldn't be this hard.