I also decided not to use the rib knit on the cuffs and just did a simple rolled hem for the cuffs and skirt hem.
I think it turned out ok. It will function nicely as a nightgown for an almost three year old. It is, at least, a nightgown not covered in fire retardants and not made from polyester. That, in itself, is a good thing. And, someday, I will try this pattern again with a different brand of rib knit.
Pattern is from Ottobre 6/2009, # 36