When it comes to these event-type episodes, Modern Family usually does something larger than normal, like the Halloween, Valentine, etc episodes. "Mother's Day," though, is a fairly low-key episode. The plot doesn't spiral out of control and there isn't a running gag which is that funny. But the episode has an underlying sweetness to it, as the strength of family comes out in the end, making the episode very satisfying even if it wasn't at the top with regard to humor.
Score: 8.8/10