In "Nice to Meet You, Walden Schmidt", Berta met Walden when he was naked, when he said 'I'm Walden', she replied 'I'm inpressed'.
In "People Who Love Peepholes", Berta agrees to be his live in housekeeper. Taking Alan's room.
In "Big Girls Don't Throw Food", Berta is very angry that Walden let Alan stay for 'a few days', calling him 'Human Herpies'.
In "Nine Magic Fingers", Berta moves out when Walden tells Alan he wants him to live with him permnantly. Despite this, she continues cleaning at the beach house.
In "I Scream When I Pee", Walden gives Berta a birthday cake at her house, with pot. Walden and Berta talk to each other and Walden tells her he loves her, with Berta saying it back. Then Walden takes her to her driveway where he shows her to a new car. Walden tells her not to tell Alan.
In "This Unblessed Biscuit", Walden and Alan think it may be time for Berta to retire when she injures her back at work. When they suggest her retiring, she grows offended, and as the conversation progresses she quits. Walden and Alan then try different maids, with little success. The two then go to apologize to Berta; she accepts and goes back to work for them.