Punkin, he almost certainly will not be happy . . . . . that is not a wish, but a strong likelihood. A good friend of mine's first h had a MLC many years ago [15 years ago, only no-one recognised it at the time] He was in his forties. He married the OW only about a year ago, so he could take her to his daughter's wedding. They are not and have never been happy together, They quarrel constantly and cheat on each other. He looks much older than he is, and his r with his kids is one of wary tolerance and financial exploitation on their part. His wife on the other hand had a very rough few years, bringing up her kids alone, and dealing with on-going cr*p from him and particularly ow, who is nutso, but later met and married another man who is wonderful. She looks about 10 years younger than her bio age, and has a great life. Because her second h's divorce was genuinely amicable [no other person involved, and he still does all first wife's diy!], he has a good r with his kids, and my friend gets on well with his first wife, and his kids.
As to reversing a vasectomy - technically possible, but not easy and not a great success rate, as I understand it. It is also very expensive, and probably not covered by most health care plans. So there you go