Lovey-Dovey is a female Black-throated Magpie-Jay that Sheldon at first feared but then adopted as a pet. This is short lived because Lovey-Dovey flew away shortly after when Sheldon opened the window to retrive her nest. She made her appearance in "The Ornitophobia Diffusion", the ninth episode of season 5. Lovey-Dovey had a nest built outside the window sill of Sheldon and Leonard's apartment.Sheldon attempting to scare the bird away
Sheldon had tried several failed attempts to scare her away, which included knocking on the window, mimicking a cat's meow, drawing a cat's face on a paper then mimicked the cat's meow again, and trying to use his "Bird Death Ray" to shoo away the bird. He later put on a helmet held a broom, opened the window and tried to shoo the bird away again. This was when the bird flew in and landed on his spot on the couch.
When all efforts failed, he resorted to Amy and Bernadette's help since they are biologists to shoo the bird away. Berandette comments that none of their education included classes on birds an dbird-shooing. The girls made him conquer his fear and he ended up being infatuated by the bird, thus the name Lovey-Dovey. He even had Bernadette took a picture of him and the bird to put it on a mug, a calendar and a mouse pad. When Sheldon decided to keep the bird, he opened the window sill to retrieve her nest and that was when Lovey-Dovey flew away. A frustrated Sheldon found his console with the bird's nest containing one egg. He eventually told Leonard that he is going to be a mother. Sheldon put up these posters around the building when Lovey-Dovey flew away.
Despite Sheldon claiming that Lovey-Dovey had laid eggs, they have not been mentioned since The Ornithophobia Diffusion.
In "The Flaming Spittoon Acquisition", the picture that Bernadette took of Sheldon and Lovey-Dovey can be seen as Sheldon's profile picture on Facebook.