I come from a family of six kids. 3 of us had children and 3 didn't. It was a decision that each of us made with our spouses. My mom and dad were fine with the decision, it was our choice. As my siblings have gotten older not one of them has regretted not having kids, their lifestyles just didn't fit in with being parents ( at least not full time ). As they have gotten older they have just adopted existing grandkids from the family and became serogate grandparents. My grandkids love their great aunties and uncles, they have so much more patience and time to spend with them. As for you mom-in-law she can find with very little trouble dozens of children that really NEED a grandma in their lives. My nickname in town with all of my grandchildrens friends is "G"-ma. I have eight grandkids of my own but dozens of extra ones. They all need attention and love ( rides, food, place to stay, shoulder to cry on, HUGS). Fraggle is a great grandbaby, my mom had dogs and cats that she called her grandkitty or granddoggy from my brothers and sisters that choice not to have children. My dad's ashes are in the family pet/dad cememtery on the property and we always call him the pet keeper. We should have listed mom's grandpets when she died along with her grandkids ( morbit do you think ) as she loved each and every one of them. Do what is right for your life, MIL will adjust.