Our little boy is pretty much normal in every way apart from being lazy in his speech - he can talk sentences like "I don't know" but doesn't do it all the time. He hardly slept at all during the night from age 1 - 18 months but we've got past that now and he's a relatively good sleeper.
However, when I get home from work and he's happy to see me (or when we have a good night cuddle) he grits/grinds his teeth to such an extent that it's a bit scary (for his teeth). The noise is tremendous.
Has anyone else experienced this? My only guess is that he can't put into words that he's happy and expresses it through the grinding/gritting. It's quite peturbing.