User blog comment:PlantyThePottedPlant/Random Topic Blogging III: Blog Harder/@comment-3006892-20130512072002/@comment-1659929-20130513233301

Phineas and Ferb (and most likely Isabella): 10

Candace and Stacy: 15

Jeremy and Vanessa: 16

Dr.D: I'm guessing in his mid 40's

Linda I'm guessing is around her early 40's.

Lawrence is probably around his mid 40's

Though presently, in 2013, I'd say

Phineas and Ferb are about 16

Candace and Stacy are about 21

Jeremy and Vanessa are 22