The two Sumatras we ordered aren't as vigorous as all the other chicks. One especially concerns me. It stands really upright and doesn't seem to want to eat. Birth defect? It can walk and run and hop over the chicks/perches but seems too skinny. The other one is visibly eating and is fatter. Is this stance normal? Its pooping but has runny stools. A lot of the chicks have runny poo but act fine. The other Sumatra doesn't stand like this one. I'm pretty sure for the most part that the runny poo is just stress. Thanks!