Corrected entry: In the early part of Fred Claus, the story teller explains that when you become a saint, you become "eternally ageless." However, when you get to the first scene with Santa Claus, he is complaining about the rest of his hair turning white. If he was eternally ageless, his hair would not still be turning white.
Corrected entry: According to the "rules," the presents must be delivered by sunrise, "North Pole time". During their respective winters, the North and South Poles have 24 hours darkness.
Correction: They do not have 24 hours darkness all winter. For example, North Pole, AK [And yes, I know the North Pole is really in Canada] has a sunrise at 1050 and sunset at 1441 making the day just shy of 4 hours on December 26. Ft Good Hope, Canada is closer to the magnetic north pole and has a sunrise of 1210, sunset 1451, amlost 2.75 hours of daylight on December 26.
Correction: Just because his hair is turning white does not mean that he is ageing.
He would nonetheless be showing signs of ageing and no longer be appearing as someone who is ageless. Even if the white hair is due to something like stress, white hair is typically associated with getting older or being old. The key to supporting the plot hole lies in the use of the words "eternally ageless." Ageless can mean eternal, but "eternally ageless" suggests he will appear "forever young." If he is ageless, he should never look "older."
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And if there is the power of eternal agelessness, there should be an accompanying ability to counteract any possible causes of growing white hair (such as stress, heredity, and dying pigment cells in his hair follicles).
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