George's sister is the daughter of Neal Lundgren and Mrs. Lundgren, and the sister of George Lundgren. She first appears in "Sue Ellen's Little Sister", racing with George in the Brother-and-Sister Race at the Annual Picnic. In the special Arthur's Perfect Christmas, she was dancing with the rest of her family. She was dressed as St. Lucy ("Sankta Lucia") in this appearance. She has made cameos in several episodes, like in Muffy's New Best Friend when she's seen on the spinning teacup ride with George and in Bitzi's Beau she's seen walking out of Lakewood Elementary School.