Well... tonight we established it is in fact the washing machine eating our baby's socks. The nerve! Impossible you say? Oh no it is very true. We own a front loading washing machine (a Maytag MFW9700S Epic, in case you too own such a beast!) and I love it. It washes clothes wonderfully, is water efficient, and takes very little soap to clean... but now I've discovered it eats my socks.
Ok what on earth am I talking about?! If you don't own this beast allow me to explain. When you open the door (which is quite thick) the space the door fits in kind of where the drum is connect to everything there is a piece of rubber that creates the seal for the door. It is NOT however a sealed piece of rubber. It is the location that if it were a dryer some lint traps are located. I've provide a stock photo below in case my rambling rhetoric is driving you batty. Now I don't have socks in the mechanics of my washing machine (I don't think!) but that space is like a black hole. A black hole for socks, underwear... you name it if it's smaller than a onesie it can and was collecting in there. Delightful!
So the next time you can't find a PAIR of socks - it is quite possible that your WASHER ate them.