Margaret the Magpie is Phineas and Ferb's second pet, who was adopted to be a friend to Perry, but ended up as his girlfriend. She is a secret agent of the O.W.C.A.
Margaret the Magpie is a saved magpie from falling out of a tree whilst she was an egg. She was saved by somebody called Professor Rokai, who would of never known she was going to be his nemesis. She was given away to a young girl on her birthday, who figured out that Margaret was a secret agent (Called Patches at that time) and had to return her to the O.W.C.A Animal Rescue Centre. She was later adopted by Phineas and Ferb, as a friend for Perry.
She really likes Phineas, as nobody cared for a bird at the centre, but soon felt welcomed by him and his stepbrother.
Same as above.
Is ok with her, but isn't that keen on her.
Despises of him, but hates her own nemesis a little bit more.
Perry is Margaret's boyfriend, and they will also work well on missions together.
Pinky the Chihuhua is one of Margaret's good friends, plus she will partner up with him and Perry if they need to group in teams of 3.