Mortar

How do we know Twilight's Mother's name?  I've seen seasons 1-7 and it's never mentioned.  Is it in season 8?

As for cutie marks, what I've noticed is how unrelated some of them seem to be to their owners.  For example, Cheerilee has three flowers with smiley faces on them, which has no connotation to being a teacher, or anything having to do with education.  Snips has a pair of scissors, which would imply he's good at cutting things (future mane stylist, perhaps?), but as we see, he's not the sharpest pair in the drawer.  His friend Snails is also a bit of a contradiction.  Snails has a...well, snail, implying slowness, which, mentally, would seem to be the case.  Yet he's a natural as a buckball catcher, which takes great agility.

One word:  Decaff.

Rainbow's expression reminds me of how Ralphie (A Christmas Story) looked in his bunny suit.