My 5-6 month old Silkie hen has recently started limping and falling over, its her right foot. She is also very lethargic. She is the bottom of the pecking order so I don't think she's been getting enough food. She's in a separate enclosure with chicken crumble and water. Is there anything else I should do? Any idea whats wrong with her? She's very skinny and when I gave her food she ate a lot very quickly.