DH and I received similiar salaries until we had kids. I think without kids I probably would have been promoted and would earn just as much if not more than him.
Instead I took 12 months off each time, went back 4 days intitially after DD was born and then increased to full time for 18 weeks before DS was born. Now I've returned 3 days a week. I'm at the same level as I was pre-kids although Ive received pay rises under our EA and increment rises. DH has negotiates substantial pay increases and based on current take home pay earns about double what I do. The gap would be closer if I was part time but childcare fees would eat a lot of that up.
I am part time and took so much time off because it was easier for me to do so because my workplace is more flexible.