Think about your favorite cartoon character... what does their nose look like? Is it miniscule like Garfield's? Baguette-like as per Wiley E. Coyote? Perhaps it's the only real feature, as in Peter Bagge's Buddy? Ren or Stimpy? Perhaps there is no nose... Marvin the Martian, or duck characters (to some extent! They have a bill...). Or maybe a weird bump like Casper? Villians love pointy noses or super-curly nostrils that they can wrinkly in disgust.
The nose is important because it's the feature that will remain constant with your character. The eyes scrunch, widen and close, the mouth contorts more than any other, the ears are usually visible one-at-a-time or covered by hair, but the nose is the center, visible in profile as much as symmetrical views. For a more realistic approach, look at Pedro Almodovar's women. They all have unique, interesting noses and their personalities are often reflected in different ways because of it. I can't make this stuff up, folks!
Anyways... here's a quick sketch simply based on size. I took away the "Homer" shadow just to make the second nose appear even smaller. Easily father and son (big nose=age?) as much as plastic surgery:
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