Tough, though choice. I had a similar sort of decision to make when my oldest (DD) was about 4 months old - nearly immediately after I returned from my leave. Now, I am not a coach in any way, but was offered a promotion at my then job. It was "the" job I had coveted, plus quite the pay raise. Despite some reservations, I took it. I lasted a year. The additional responsibility (and for me, travel) was too much for me. I just missed my little girl.
One disclaimer: my employer was in no way child- or family-friendly and was also a 45-minute commute on a good day, adding to the time away from my infant. My job also required a lot of travel - a good 3-5 weeks per year and that amount continuously increased. All things you may not have to consider!
Just thought I'd throw my experience in the ring. For me, I can't help but wonder if I'd still be working there if I'd never taken the promotion.