Boxes, a place where you can let your imagination run wild. I remember playing in plenty of them growing up, turning them into cars, houses and such. Although Maggie is a bit shocked at Kara's choice of things to pretend to be.
For those of you who dont remember Kara is Sara's younger sister, and the keen eyed among you might notice she also got a total redesign. So no longer does she look like a miniature Sara clone and is now a proper combination of her parents.
Continuity Clarifier: This doesn't fit within the continuity of the comic since Maggie's and Kara's whereabouts are currently unknown. Given Kara's approximate age of 10 in this picture it means its taking place roughly at the same time as the comic story but in reality these two wont be doing this well when it comes to possibly bringing them into the story.
This drawing is based on an idea suggested by CidYoshi