I have 4 new chicks, they are 5 weeks old. 2 buff orpingtons, 1 barred rock, and 1 americauna. 3 came from a local breeder, but one arrived via mail, her name is Shortcake (she is a buff orpington). She originally came with 3 other mates but the other 3 died in transit, so I know she had a rough journey. When I got shortcake, I was so concerned about her wellbeing alone that I found the other 3 chicks nearby, and was told they had just recently hatched and figured they could all brood together and form a new flock. They were all about the same size when they first arrived. I boosted Shortcake's electrolytes and probiotics to try and encourage her health and growth. They are now 5 weeks, and the 3 local chicks are growing well and almost fully feathered. Shortcake is still quite small, about the size of the other 3 when they were 2 weeks old. She is feathering, but her feathers are coming in very poorly and look ragged. She eats with the others, and fights for her treats when provided. She is feisty, but just lagging in size and appears a little weaker then the rest. Do I need to worry? I thought if she survived past 2 weeks she'd be good, but this has been a struggle since day one, and very draining on my nerves. I am so afraid to lose her, but would like to know the honest truth about her prognosis if there are skilled and knowledgeable chicken raisers out there who have maybe come across this before. Her pictures are below for further reference. Please and thank you for any help and advice!!