Because they are step-brothers they have different grandmothers.
Phineas' is named Betty-Joe Flynn his grandpa is Clyde Flynn. Ferbs' is Winifred Flecter and his grandpa is Reginald Flecter.
Flynn
Ferb is Phineas's stepbrother. Phineas's mom married Ferbs dad.
Ferb is the stepbrother of candace.Phineas and candace are real siblings.
The stepbrothers Phineas and Ferb live at 2308 Maple Drive.
Richard O'Brien plays Ferb's dad and Phineas and Candace's step-dad and linda's husband
Grandpa Clyde Flynn and Grandma Betty Jo Flynn are Phineas and Ferb's grandparents.
Flynn
Her full name is Isabella Garcia-Shapiro.
Caroline Rhea is the actress that does the voice of Phineas and Ferb's Mother.
Perry the platypus
No it is actually their inventions
dave moon
Phineas is voiced by Vincent Martella. Ferb is voiced by Thomas Sangster.
Ferb is Phineas's stepbrother. Phineas's mom married Ferbs dad.
Her name is Linda Flynn-Fletcher. But if you are referring to her stage name when she was an 80's pop singer, it's Lindana.
Disney Get Connected - 2008 Phineas and Ferbs DS 2-1 was released on: USA: 1 February 2009
There Father's Name Is Lawrence.