Cute! Pippa is TINY! Do you have any day-old pictures of her? I'd love to compare them to my runt-silkie. (I'll search the threads for more pics :-D)
3 weeks sure is a funny stage, yes? Feathers and down.
(Edited to Add: Wow, I never thought I'd say this, but I think my runty silkie was actually smaller than Pippa! Holy Snickerdoodles! I'll have to go out and put her on the hay scale to see how much she weighs at 3.5 months) But they are all going to grow up to be fabulously beautiful chickens!