Sorry but YABU. He won't have know it's value, he won't know what he's done with it. Getting grumpy with him will not work, softly softly playing hide and seek games may work. Have you looked in his toybox? bed? paint box?
Yes YABU. I left my wedding and engagements rings on my computer desk once when I was having a shower. My kids got hold of them and although I found my engagement ring my wedding ring has not been seen since. This was 6 weeks after our wedding. I asked them where it was but they did not know. Mine are 4 and 2 but I did not have a go at them. I shouldn't have left them there in the first place. Bad luck but at least you know it is in the house somewhere. It will turn up one day as will my wedding ring no doubt!
you've probably thought of this, but could it have been lifted with something else you put on top of the drawers? I lost my engagement ring when DS was only a couple of months old. I found it in the wastepaper bin in the bedroom, wrapped in a used face-wipe!!