If a child has demodex, is it possible they might get them from contact with other children? I don't know if your 3 year old has siblings, or is in pre-school or babysitter with other children, but so many things go between children--that's something to ask too. In case you cleared it up and she got them again in the same environment. I may be way off, but I know someonw with several children and some are in elementary school and they have had a problem with lice. She is having a terrible time clearing them up. I think the problem is that it's not necessarily the lice that creates the problem, but the nits that attach to the hair. That may be a bad example, but just showing how little ones spread disease among themselves.
Good luck in your pursuit. Lucy
Don't trust any refractive surgeon with YOUR eyes.
The Dry Eye Queen