Friendly Germs?

Bara gave the kids their Christmas gifts early this year since she's travelling over the holidays.  Ehren loves science, so Bara and I thought he would love his present, "Disgusting Science."  When he first opened it, he said, "What is this?"  Bara explained that with it, you could grow germs from your own body.  Ehren said, "germs?"  He looked puzzled.  She went on to say, "germs from your skin, friendly germs, all kinds of germs."  He put the kit down.  She continued on about how exciting it would be.  He carefully backed away from it.  With every word, he looked more horrified.  "Mom, do I have to touch it?"  I thought he might cry.  Christian chimed in, "I want to try it."