I am afraid of the red bleed in that dress. I would probably cheap out and just have her wear it without doing anything! I mean, unless its dirty it stinks or something.
I bet the other kid wore it for 2.5 seconds for pictures. I wouldn't worry about it at all. Is the silk kind of stiffer feeling or is the soft limpy kind. Hahahahahah,!,? That sounds nasty
I've washed silken dresses from Janie and Jack before with no problem. I just did as you said- delicate cycle on cold. No red, but there was one with bright purple flowers and I didn't see any bleeding.