Season 1, Episode 4: Return of the Shirt
Ted dated a girl, Natalie, three years ago and quickly got annoyed by some of her antics. Therefore he broke up with her, leaving a message on her answering machine on her birthday. His blamed his behavior on his immaturity and after being forgiven by Natalie they end up getting back together. Robin meanwhile realizes that no one is interested in her show and plans to do or say crazy things which Barney dares her to.