Evil genius or just bad brother?

Because of Isaac's allergies, we always keep Benedryl in the house. We used to have to fight and bribe him to take the medicince when we saw an outbreak coming on because he absolutely hated it.  About nine months ago Isaac realized he could swallow the tiny allergy tablets, so we don't even keep the liquid stuff in the house anymore and we haven't had a fight since.  The other night Isaac was having a strange reaction to something he'd come in contact with, so I handed him his medicine and told him to take it.  Instead, he grabbed Genna's soda, poured it into a cup, and dropped the allergy pill in.  Completely puzzled, I asked him what he was doing.  His reply, with an evil grin: "I'm melting the medicine in pop for Nahshon.  It's going to make him nice and sleepy"  Ok now, Nahshon is in his terrible two's, and his mood can go from happy to sad to excited to angry in the blink of an eye, but this is a little over the top!  I honestly don't even know where he got the idea because we have NEVER dissolved medicine in anything before.  (I wouldn't be surprised to find out they learned it on PBS kids though, they spout out all kinds of random knowledge after watching those shows)  Not to worry though folks, I dumped it out before he could carry out his nefarious plan.