Aw, God love you trying to help this wild creature....
A few years back we heard loud- I mean LOUD 'squeaks' of distress from Magpie birds in our front garden, we were stunned at how loud they were- wondered what was going on??
Upon closer inspection, I saw (I kid you not) Magpies practically throwing themselves at the house, in distress.
Amongst all this chaos, we find our cat- Ginge, perched on the Little loos window ledge, calm as you like with a fledgling in his mouth. We let him in to the house and Plusone wrestled the little bird out of his mouth.....
All we could do was capture the tiny little thing- who was not moving at the time (dead)? and 'park' him at the bottom of the tree where his parents resided (all the time the parents were still like wailing banshees and flying down really close, in attack mode.
Anyway, several weeks later- we realised that we had 3 Magpies in our tree...best feeling ever
They have since moved on but I like to think the ickle one survived.