Hello C.,
I don't know how to treat fungi in babies, so there is not much I can tell you about that. But what allot of people do not realize is that finger nail and toe fungi can be spread by using nail clippers that someone with nail fungi used. My sister has bad toenail fungi; and without thinking, one day I used her nail clippers; (even after she told me not to) Anyways, I ended up getting the fungi, but only on two of my toenails, (my second and fourth toenails) My husband, our daughter, and I have separate nail clippers, that I labeled with our names so there is no confusion on who's who's. Just thought I would share that info with you. Good luck.
A. Z.