Being the parent of a child with special needs, be they medical, behavioral, or psychological is difficult at best. It also can be incredibly isolating for the parents of the children as they realize that they can hardly ever leave their home because there isn't anyone willing or qualified to care for their child safely. This takes a toll on every aspect of the parents' lives and is incredibly... well.. it's just awful, and it puts a lot of pressure on the parents' mental health, no matter how much they love or how well they care for the child.
If you're looking for the best, most meaningful, most wonderful gift you could give any friends you have who may be home caring for a child with special needs, perhaps you should consider putting in the time to learn what you need to know to safely babysit the child so the parent(s) can occasionally get some time away.
