I dont know what to do...

Tonight DS told me 'teeth sore' and then 'brush teeth', so we went to brush his teeth and the front one has a chip missing out of it!!!!!

It must have happened today while he was with mum, but she cant think of when it would have happened, unless it was when he was playing in the backyard with a relative. But they didnt notice blood etc or anything and he didnt complain about it.

The piece missing is like a little rectangle at the bottom, maybe 3mmx1-2mm but its noticable.

Do I take him to the dentist to get it checked out? Its a baby tooth but still, I'm worried about whether it needs to get sealed over etc?