I've got a very applicable story... [EDIT: which happens to jibe with Keith's point above. LOL]
As a 37yo married with 2 kids, I've always been close to my older brother who is now 41. He got a full ride through the Army, became a dentist at OSU, endontistry spealist through Army...all on a full ride. He was sick of the military and bailed out. Bought a endodontistry practice in northern VA and is killing it $$$ but is sick/depressed.
He met a woman online who just happens to be a 41yo widow with an 8-yo son. She's a high-up at OSU School of Medicine and lives nearby. Now, after never seeing the guy for the last 20 years, he's up in C'bus almost every other weekend to be with her:leghump:. She and her son are also awesome people.
Within a few months they are already casually talking about him selling his practice and moving to C'bus, getting married, etc. My parents couldn't be happier, and it's an absolutely amazing situation for my brother who we thought for years might have been gay with the lack of GF action he had.
I say all of this because literally, this guy started off 2015 with no kids, no marriage and a life situation that made him depressed (despite what outsiders would think is an awesome, big money gig). Now, after meeting them myself, I absolutely couldn't imagine a better situation for my dear brother.
TL;DR? Don't consider getting a younger wife to be the game plan...just live YOUR LIFE and, if something is meant to happen, it will. No need planning for something that is best left to karma/kizmet/whatever. Way more professional women with kids that you could marry into than thinking about getting your own offspring at 55 through some needy bish in a totally different life situation than you.