There have been a number of mermaid Barbies over the years; so many that even though I have previously referenced them in posts, I could not even begin to catalog all of them.
If we were to set our sets back 30 years to the glorious days of 1993, a number of mermaid Barbies (and friends/family of Barbie) present themselves.
Fountain Mermaid Barbie is notable because she has a gimmicked headpiece that sprays water - hence the name "Fountain". Judging from the picture on the back of the box, the mechanism for this is a hand pump - the water goes in a higher or shallower arc depending on how you squeeze the shell.
Also from 1993 (though some sources on this one say 1992) was Magical Hair Mermaid Barbie. What was "magical" about her, you might ask? Her hair changed colour in water of different temperatures!
Her hair turned purple in cold water, then pink in warm water. Notable is that this is described on the box as "turning purple" and then "back to" pink, but in almost every picture I've seen of her she already has purple hair. (Including on the box art - although to be fair Mattel and I might not see eye to eye on at what point a shade becomes "purple" or "pink".)
Featuring the same colour-change technology is Mermaid Skipper and the Sea Twins.
In this case, the tails of the baby mermaids and the fins at the ends of Skipper's tail changed colour - according to the commercial, to pink in warm water and blue in ice water.
Interesting to note is that one Amazon listing I found describes these as "Krissy-type Baby Dolls", but the character of Krissy didn't actually debut in the Barbie line until 1999. So technically you could say that Krissy is a Sea Twins-style Baby Doll.
I dunno why you would, but you could.
But specifically, Mermaid Skipper and the Sea Twins is fascinating to me because... well, do you know this reaction picture?
According to some reddit sleuths, this has been identified as Mermaid Skipper from Mermaid Skipper and the Sea Twins.
(With a face filter, obviously.)
