Time to pop em out
I guess that if everyone is right about this being likely to affect his career path with this employer, the obvious solution is to embark on the creation of a larger family, maybe look at taking shifts for the next few years - 4 weeks on, 48 weeks off, with 2 for the Mrs?
If he get's his timing right so he is rostered over xmas/new year to take advantage of the public holidays and general feebleness of organisations at that time of year, management might struggle to schedule too much vindictiveness into the small work windows in his schedule.