When Phineas and Ferb bring Candace to the stage to have her sing "Mom, It's Your Birthday", Candace puts her hand just below the microphone. In the very next shot, her hand is on the microphone itself. In the next shot her other hand is below the microphone, and in the next shot (and for the rest of the song), both hands are on the microphone. Candace could not move her hands so fast.
You see Candance play all the instruments that begin with the letter B she owns and exists. The time card says "5 minutes later..." but she couldn't have been playing those instruments for that long.
Phineas' flashbacks of himself reminding Ferb not to forget Linda's birthday are shown to take place during the events of "Rollercoaster", "Are You My Mummy?", "The Magnificent Few", "Lawn Gnome Beach Party of Terror!", "Flop Stars", and "It's About Time!"
When Phineas is handing Mom the magazines, he hands her "Mom Biweekly" when he says "Mom Weekly" and "Mom Weekly" when he says "Mom Biweekly."
Candace can play the bass, banjo, bagpipes, bongos and coincidentally, almost every instrument that starts with B
Isabella appears in the episode, but we do not actually get to hear her speak.
Isabella was shown on the stage performing, but she was also in the audience at the same time.
Musical Song: Mom, It's Your Birthday
Ferb:(about the birthday card) It's a simple, post-modern fusion of origami and pop art.
Doofenshmirtz: Behold, Shrinkspheria! I was going to call it the Shrinkenator, but I've used that enator suffix way too much already.
Doofenshmirtz: Pelicans. Terrible creatures. What are you a bird or a garbage disposal?
Mom: What a beautiful breakfast.
Phineas: Made with love.
Buford: And, sweat.
Mom: And by "sweat." You mean hard work.
Buford Uh, sure.
Doofenshmirtz: I love it when dreams fail.
This episode is set to re-air May 10th.
This episode replaced Journey to the Center of Candace.
The Horse Whisperer:
There is a DVD in Doofenshmirtz' lair titled The Unicorn Whisperer, parodying the 1998 film The Horse Whisperer.