Is it actually the element or is it a homeopathic preparation? The only time I've ever heard molybdenum talked about is in relation to the radioactive isotopes, so from that view point I would be very cautious about using it without a detailed explanation...however if it's a a homeopathic preparation, they are usually so wildly dilute that i'm not sure they would even contain even trace amounts of the thing they're made from. Is she trying to use it to chelate the heavy metals (from the vaccination) out of her system?

Either way, it's a good idea to follow your intuition. xxx