We found out on last night's How I Met Your Mother that Ted has a sister, Heather (Erin Cahill) and that he has apparently been hiding her from Barney (and us!) all these years. However, when Lily let's it slip that she's in town, Barney finally gets his chance to meet her.
Oh, and, meanwhile, Marshall and Robin have their own little adventure when Robin gets homesick for Canada. Catch up on the full episode with our "Little Minnesota" recap.