 Povenmire also characterizes him as assertive, someone so secure in his abilities that others assume he is a prodigy.Povenmire and Marsh wanted the series to reflect their own childhood memories of going out during the summer and have fun, digging trenches and building tunnels, forts, and tree houses.The creators wanted Phineas, like Ferb, to be a character who would never "[do] anything with any animosity," or to agitate his sister or outsmart his mother purposely.