Princess Velvet Dawn

Second born daughter to Princess Twilight Sparkle and Royal Captain of the Guard Tempest Shadow. Velvet isn't one for silliness and roughing around. Her mother Tempest Shadow fears she is too reclusive, and her Mama Twilight Sparkle believes she will find her own path eventually. It's not like she never goes out and plays with friends, it's just that she is usually the one making sure nopony gets hurt or gets into trouble. 

Basically, she's the mom of the group (much to her mothers' dismay).