A week ago today my partner brought home a baby sparrow that he saved. We fed it cat food like most internet pages said to do. And I had already raised a sparrow on dog food a few years back (which is still alive and kicking today, almost 3 years on.. )This one was a few days older than my other one was, but he took to use and we fed him with a syringe. He got bigger and stronger everyday and appeared he was getting ready to fly.I was very attentive and fed him constantly, taking him to work with me and everything.we ran out of cat food, so grabbed some dog food on our way out for dinner where I fed him in the car before dinner and after. But he didn't eat much (maybe didn't like it?) Then it was late and bed time.The next morning, I was rushing and busy, and only got to feed him once and he wasn't really taking to the food, so I let him be. When I got home I put him in a cage so he would get used to being outside, but he stayed curled up in the nest I made of sock material. I starting doing something around the house and noticed it had been over an hour since I checked him. When I did he was curled with his legs up and eyes closed and looking like he was on the way out. I freaked out and tried to force feed him as he appeared weak, with some insectivore mix that a pet store recommended. He had trouble swallowing. I don't know if that made the situation worse. I just thought I was doing the right thing. I kept him warm wrapped up in warm material in front of a heater. He finally started opening his eyes after over half an hour and things appeared to be getting better, then still with his eyes open, he made last attempts to move which appeared very hard and painful. And then he rolled over and died! :(I can't stop thinking it's my fault! If I had of paid as much attention as I did every other day, maybe I would've noticed he wasn't doing well earlier. Maybe I choked him trying to get food into him. Maybe it was the change of food. I'm not sure, but I can't stop feeling guilty! One day his fine and moving more than ever and the next he dies.. Why?

Yes and no.

Perhaps he had a illness you were not aware of. Change in climate and temperatures going inside and outside. Being in contact with humans and virus and illness they have that the birds may not be in direct contact.

The change in diet may have caused trouble, and a 100 other issues.

You tried to save a bird that nature would have normally allowed to die. You did your best.