I think we need to cut this family some slack. As a society we need to be willing to accommodate people with genuine needs like this. On the other hand, I have no patience with those who travel with too much luggage, those who think they're taking a stroll in the park and those who insist on taking pet rabbits & peacocks to allegedly alleviate travel anxiety.

The equivalent of this is when I encounter bad drivers on the road, I get mad at them unless the driver is a senior citizen (in a car-centric culture we give them no choice but to drive) or has an otherwise visible reason to be distracted/slow/etc.