I have five roughly 4 week old chicks. Three EE and two SFH. One of the SFH chicks started arching neck downward yesterday and doing what looked like some crazy chest preening. So much so, she's almost doing a somersault. Seems to be eating and drinking, but just acting strange with curling over and backing up at the same time. I felt around last night and her crop was pretty firm. I massaged it and gave her a little olive oil by dropper. This morning it was still pretty large and firm, so more of the same. All they have to eat is chick starter with access to grit. They are in pine shavings, but I haven't seen them eating them. Any ideas how to help/ clear crop out? Thanks!