Hi there - I got 4 chicks on 3/16 - now, a week later, 3 of the chicks are plumping up (50% larger than last week) the fourth chick (Barred Plymouth Rock) is a little lethargic and hasnt gained nearly as much in size (maybe 10-20% bigger). She eats a bit, she drinks a bit, her poo is generally as solid as the other girls. The other girls are an easter egger, a silver laced wyandotte, and a buff orpington. Any info - is there something I can do to coax her along? No pecking or aggression is occurring from the other chicks. thanks!!