Hi
I found a Blue Tit chick on the ground in my garage this morning - it looks healthy and is calling out. Should I just leave it alone as a parent may be nearby?
Leave it alone.
The parents will be around, and it may have started to fledge, finding its wings.
You will see the parents, who will be very concerned for its welfare coming to feed it regularly, and if it is starting to fledge, then it will soon find its wings and fly back to the nest. Either way, the parents will continue to feed it until such time.
While there is a risk of predation, harsh it may seem, that is nature.
Mike
Flickr: Peak Rambler