Raise my kids. No doubt about that. Way more difficult than I thought it would be. Not bad, but just a lot of work and it can tear your heart out. Starting with giving birth, (after difficult pregnancies) colic, killing myself learning to breastfeed, being up most of the night, taking care of a toddler, taking care of a toddlers and babies at the same time, 3 year olds (OMG, the worst until you get teens) and then having an other one when we thought we were done, teens, through college and it's still not over! Our "baby" is still in Grammar School.
Friends tend to go away when you have babies (especially since we had kids before most of our friends did) or at least you find out who your real friends are. It's hard being "responsible" when all your friends are still playing and partying, (but, honestly, I'd rather hang around with babies than dopers anyway) then we had an other baby when most of our friends were done with the whole baby phase.
Putting your career on "hold" until the kids are old enough to go a few hours without you, then realizing your career may have passed you by and the economy crashed while you were busy raising people who certainly couldn't do without you. The economic strain is great. Latest word is women who stay home to take care of their children may lose out on about 1 million dollars in income, due to not being in the work force as well as everyone who hires you thinking "Mommy Track."
It can tear apart or strengthen a relationship, depending on how the two of you parent together.
Worth it, of course, for us. But, damn, I didn't realize how much work (and money) it would be.