Upset elderly neighbor over smoking

Ri

We have befriended an elderly neighbor without any living family in our country. He's a widow and recently his beloved dog died as well. He's much older and where we live is rural so having a friendly face around when needed is important in case of bad weather or trouble.

We like him our kids hug him. I've baked him cookies made him homemade lemonades and grape juices. He has come over for dinner. He even gifted me his late wife's family glassware.

We like to invite him to our home as we have children and he is a heavy heavy smoker. Recently he asked my husband to bring over the kids and come to his home. My husband had to explain that it wasn't possible because of the smoke in his home to bring our kids there. This elderly neighbor was so heart broken and kept saying his home is clean he's clean. To be fair he keeps an extremely tidy home and he is very meticulous. We tried telling him that it's just the smoke isn't good for the kids.

He is so upset. Now with snow out he won't come out of his home much and I'm worried about how lonely he will be. What can I do? I can't place our kids and babies in hazmat suits to visit him lol but he has been smoking for over thirty years in his home and he's a chain-smoker just to give you an idea of how bad his home is we get sick being in it so definitely don't want my kids in it.