Hi just a suggestion u might wanna take the tiel baby to see a Avian Vet to be sure it isn't a sour crop. I had tiels in the past who bred and my experience is that the baby birds can go bad fast and you can loose them. Yours looks ok and healthy but you might wanna get a Avian Vet to look at it to be sure and this will give you a chance to ask any questions you might have also. Good luck!