I wouldn't be too worried hun. If he's anything like my DS, I suspect it's more that he's imitating for the novelty value than anything else. There is probably an element of attention seeking, but I wouldn't be too worried. DS1 loves to copy anything and really that is normal, they learn from imitation. I would go along with it. Make him some "tablets" to take - I'm not sure how good his imagination is, but pretty much anything would do I suspect, maybe even sultanta or something. Just call it a "tablet". See you go with that. If it works he'll probably be really happy to be included and then the novelty will wear off. And I personally don't think that it is going to give him the idea that sick always equals tablets. I think as he gets older and learns from what you do more, he'll understand that there are other options.