Lucky girls to have you! Pekin are prone to foot/leg problems because they are BIG. Your girls are lovely!!! And cute names! My ducks all have food-based names: Figgy (Runner), Clementine (Swedish), Marmalade (Welsh Harlequin), Peanut (Saxony), Julep (Pekin), and Cheddar (Call).
My Welsh Harlequin didn't limp, and she had one if the worst infections I'd ever seen. I felt so bad for missing it! I made a lot of changes to their environment, and it hasn't been a problem since. Now I slather their feet with lanolin every few days. That's made a big difference! Their feet are soft and smooth now - no cracking or roughness at all.