I love my donkeys - had them for years and would never be without one now. Such l;oving little charactersx they all are
Firstly the lung worm old wives tail - no your horses will NOT get lung worm off your donkeys so long as ALL are wormed regularly and correctly. I have never had a case of lung worms in either donkeys or horses in over 40 years of keeping both together.
Mine live out all year round with Dolly, but they do have nice waterproof rugs on as they do not have a natural waterproofing in their natural coats. My fields also have a lot of natural shelter that they do use. They have to have their feet trimmed just the same as a horse does, and their teeth seen by a dentist too, but I only have theirs done about once every two years, they just don't seem to need more regular attention. Their teeth that is not their feet obviously!
Although mine have not had any regular interaction with children, the odd time I have had mini visitors they are very gentle and calm around the kids so unless the child is obnoxious I cant see that would be a problem. One donkey will be perfectly happy without another donkey in me experience, so long as it has the constant company of another horse or pony. Bertie lived for many years just with Solly and was very happy and contented. We did get Joseph to keep him comp nay in case he pined when Solly died, but he is more interested in hanging about with Dolly than his little donkey friend.
They can be noisy - but mine only shout if I am late down to feed them in the winter, (they only get hay nothing else, ever) in the summer on restricted grass alongside Dolly...but not much shouting then as I am not the bringer of food at that time of the year!
We have several donkeys dotted around the valley I live in....we do get the odd day when they all chorus and call each other, but it really doesn't bother anyone because it is very much a rural area and just part and parcel of keeping livestock.
Gosh I have waffled on - hope it helps!