Help! Underweight cockatiel baby

[Limiju]

She is absolutely beautiful!!!!

I believe Angel will be the darker grey pearl pied, like her mother. And I am calling her a her as I read somewhere that if she is hissing at the young age it normally means she is a girl. I will see as she grows up.

 

[MikeyTN]

Here's something I've personally noticed, my momma birds that eats mineral block and cuttle bone feeds it to their chicks too and the pair that didn't do it have problem growth with their chicks. So I put another pair breeding with them and they have changed their ways and started eating the cuttle bone to feed their chicks too and now growing healthy. I have done several stunted chicks but I usually move them to a different pair to care for as they turn out better. But if I don't have another pair having chicks I remove them to hand feed and have successfully raised them. One of the girls I raised out of last batch was like that. She was about 45 days old before she fledge which is about 10 days behind. My chicks start flying around 31 days old.