Pin Trading - How little is too little?

[Alexsmommie]

I started seeing some of the pins available for pin trading and I'm hooked! (I'll probably end up saving more than I trade but we'll see how this goes...) anyway I thought about getting a lanyard and some trader pins for my son (2 a few weeks from 3 by the time we go) to trade but lately he's been into this mood where I don't know if he'll get too attached... plus they are pins afterall and I don't know that I want him to have them on his own (because he may want to take them off the lanyard and play with them which can be a big distraction not only for him but for me as well!) so how little is too little? Has anyone ever had experience with pin trading and children? If so, how little were they and did you just trade for the pins for them instead? Thanks for the input!!!!!!!