Okay:
Your In-Law is terminally ill.
They are old.
They are not well.
It is very taxing.
My Dad, before he died, was very ill. Home-bound. He also had had a stroke. My Mom was always stressed. We ALL took care of him. It took me/my Hubby/my Mom.. to care for him. That is 3 people. It taxed ALL of us. It was at home and driving him around to appointments and Dialysis appointments and everyday caring for him. Feeding, medicines, bathing, etc.
Very tiring.
It is not like, we were in the mood, to entertain people. Nor happy to rush around getting the home cleaned up and food prepared for any guests. It is very... STRESSFUL.
So, I can see how your In-laws, feel.
They have SAID, they don't want, visitors.
They are being, open.
Speaking for myself: IF someone, relatives, insisted on coming over and spending a length of time at our home, with their kids, WHILE we had told them we prefer no visitors and cannot handle multiple visitors with kids, and only in small amounts... and IF those relatives STILL insisted on coming over and did so. I would be, SO irked!
Because, they were, blatantly disregarding, our/my family's/my late Dad's wishes.
We, did not like being intruded upon, in our own home, with my Dad ill and not well and us fatigued and stressed from the daily care-taking of my Dad.
And we were all very busy, doing so.
Your Husband, needs to understand this.
His parents, have said, their wishes.
Sure, you can visit. But go according to THEM.
You can explain to your kids, that they are old/not well, etc. But they are very loved. Try making things with your kids, FOR them. So they gain a sense of empathy, for their ill/elder grandparents.
YES, they should WANT you to visit. And especially with kids, around.
Sick/ill elderly... also need to sleep, and rest a lot. They do NOT have the energy, to even breathe, sometimes or even stay awake.
Gosh, I can really relate, to their wishes.
I hope your Husband, can too. One day.
And not take it personally, that as his Wife, you are not listening to him or disagree.
Or, HE should be the one, to go and visit HIS parents, WITH the kids. Since those are 'his' wishes.
Next: How come your Husband's parents, have no care-takers for them, in their home???? They need one. A Home health aide at the least. They cannot manage, on their own. It is their health and it is not safe.
Your Husband and/or his siblings, need to get their Parents some help. It is also, a safety issue.
Your MIL, has Dementia.
People like this, NEED TO BE supervised.
It is very dangerous, for them and others. They are unpredictable.
Her Dementia is from her illness.
They need care-takers at their home. Daily,
Professional care-takers.