Good for you! I'm happy that you have given your family and cat a more fulfilled life.
I know that there is an over abundance of cats in the world but a litter of kittens is a WONDERFUL experience for your family and your mother-cat.
There is a difference in animals who have been mothers. They are usually more settled and nurturing. (Farmer. I know animals) Your children will never forget the time that you spend with them and it is a beautiful learning experience.
Regarding the "already too many" issue, i recently adopted a shelter cat and he is the first one that isn't a disappointing pet. I have done my "duty" adopting 5 or 6 cats and they are usually a bit mental. We have a 15 yo cat that we raised from a few weeks old. He is still a pain to pet, spits and drools and tries to crawl up my face. Wont stay in the house and kills rodents and birds with relentless tenacity. I picked up a dead baby bird this morning at the bottom of the stairs. Neighbors hate him, he isn't kind to the other cats or dogs. But he is better than the two who refused to come out from under the bed. I hear adopted dogs are better but I'm not brave enough to try it.
What I'm trying to say is that rescue cats, even early rescues aren't often socially adept. I was having Empty Nest syndrome, couldn't afford a siamese or i wouldn't have tried new rescue cat. He was raised by a university student and reached for me from the cage. I couldn't resist.
You are doing some of us a favor by giving the world "normal" cats that aren't expensive breeder kittens. I searched for two or three months for a normal, family raised kitten like yours.
Also, some adoptions are ridiculously expensive and intrusive. Before we found this cat, dd called about a kitten at a pet food store. The owner/adoption person required taking 2 kittens, not one, wanted paperwork from my vet on ALL of our pets and wanted 2 or 3 home visits, blah, blah, blah. Erhm....NO!!
Ignore the naysayers, you are a wonderful mother and responsible pet owner. Enjoy the experience with dcs. In the "Old Days" pets giving birth and then raising puppies or kittens was an intregal part of learning how to nurture babies, facts of life/birth/possibly death and parents teaching so many things about taking care of vulnerable little babies. I wish that i had been able to do so with my dc. My dh still fondly remembers when his dog had a litter of pups.
I'm sorry to ramble but the world is being sucked dry by the social/political/environmental policies that we are placing on ourselves bc we listen to slogans, celebrities and media echo chambers. We need to think independently with practicality about things instead of listening to loud voices spoken with authority.
Simple pleasures are being swept away. It's not good to voluntarily give away simple, normal experiences.