why do babies need teeth anyway?

I am confident I can count the number of nights Seth sleeps straight through in any given month with the fingers on just one hand. Without using my thumb. The recent culprit seems to be teething, and you have to feel bad for the little guy, when he's teething it's like his whole head fills up with fluid. His eyes water, his nose runs, he drools like a maniac, gets ear infections, and has other cold-like symptoms. And of course, all this comes along with some pretty short spans of sleep at night. Usually it lasts for about two weeks until a little tooth pops through, and then all of a sudden he turns into fun, happy, I can sleep at night Seth, for a couple days until the next one starts. And then two more weeks for that tooth to come in. Four down and a whole mouth to go! Please pray for our sanity :)