I think having kids later in life can be great, and without the stress of financial insecurity it would be even better. Imagine having kids and never once having to go without in order to take the best possible care of them
A lot of it depends on his financial circumstances and family support. If he can hire out some help and occasionally pawn off the kids to rest up a little it should be ok. Tell him to do some aeorbic exercise now to improve his stamina, etc. It will be tough but it can certainly be done.
He who makes a beast of himself loses the pain of being a man
They're gonna be almost 60 when their absolute hellion of a daughter goes out and tries getting herself knocked up by some creepy old fucks because she has daddy issues, will they have the energy then to rein her in?