Board Thread:Spoilers!/@comment-26443838-20161212210741/@comment-24674051-20170308174512

Who knows how mermaids age/don't age. I mean Ursula is at least almost as old as Killian, yet she appears to have maintained a young adult appearance, and she was already an older teenager when she first met Killian. And Ursula, to my knowledge, did not spend time in Neverland.

My guess is that, like many immortal and long lived creatures, they age up to a certain point, and then go into a holding pattern.

So, I don't see any problem with Ariel not aging.

Besides, Jasmine is current to the rest of the storybrooke gang, since we know that Aladdin was caught in the original curse. So there is not that much age difference between Ariel and Jasmine. Probably about the same as Ariel and Snow.