It was pointed out to me (ok, not particulary to me) a long time ago, when I was lurking in deviantart.

It's pretty obvious.

Only in the original TLM though.

^They seem to have the same faces in the prequel too. That screencap is of "Ariel's Beginning".

Yeah , But it didn't put any force on them so I didn't mind it.

Yep.

I noticed that. But they all got that same face from Athena, Triton's wife. So, since Ariel and all of them are siblings, and they all have the same mom, it makes sense to me. Gene pool science alleles thingy.

^That doesn't make sense: they can't all have the exact same face as their mother. They aren't twins and they have a father too - they must get some physical characteristics. And how would alleles explain the absurd difference in hair colors: one redhead, one platinum blonde, one golden blonde, two auburn-brunettes and two dark-haired girls?

^^Their faces aren't all exactly the same! They look the same from a cursory glance. But some of the faces are a little pudgier than others. The daughters would get some characteristics from Triton who has a pudgier face. How much do you know about alleles? If Athena had multiple sisters, herself, she could have had several different alleles at the same locus for hair color--- explaining all of the different hair color combinations in her girls.

Anyway, I'd go easy on this. It's not a big, big deal.

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Their faces are exactly the same. Only Alana looks a little different in this pic because of the facial expression she's making. And no, the drastically different hair colors are not explained that easily: let's say, if Athena was aa (platinum blonde hair) and Triton was AA (black hair - and I'm just making this up and I know that these are not the hair colors shown in the prequel), the possible combinations would be: AA (black - Alana and Adella), aa (platinum blonde - Arista) and Aa (brown hair - Aquata and Attina). As far as I know, that's how alleles work, and it would still not make sense for Andrina to have golden-blonde hair and Ariel to have carmine-red hair.
And finally, you're right: it's no big deal. They are minor characters and the WDAS was nearly bankrupt when they made "The Little Mermaid". However, your explanation doesn't make sense. If everything coul be justified by "they inherited their mother's face" and by "gene pool science alleles thingy", it could also justify Anna and Elsa having the same face, and also many other similar cases done by Disney and other animation studios with their female characters.

^^^ Which is exactly why I said it was no big deal. It's a minor grievance. Like you said, Elsa and Anna have basically the same facial structure, and it's just Disney computer animators getting lazy and then COMPLAINING that "it's too hard to animate female character's faces." Boy. They sure love to complain about their own laziness, don't they? LOL.

*Roll eyes* You never said that. At all.

It's blatantly obvious.