Your town happened to be the home of what people call the merfolk coast. An unusually clear-skied zone (As in no matter what during the day the clouds hardly ever went overcast) stationed above a pristine beach of beautiful sand.
But the name came from visitors besides those like your family or maybe just like them at times. For there were a series of pools littered about the area both outside and within easy access and stabilized caves that had the mysterious ability to turn users into merfolk and back, no really these pool do that. What’s more many of the homes and local businesses, your family’s current summerhouse among them, had these access points to a deep water tunnel system that allowed transformed access though for legal and safety reasons the houses ones have security gates that require keys or permission to open.
“Wow... I can’t believe we’re finally here” Your older sister Jessica called out as your family car pulled up to your current residence and got out as she took a good long look at the open sea out front. “You interested in trying out-” you tried to ask. “Hay if anyone’s planning on going ‘mermaiding’ if you know what I mean it best be done in groups” your older brother and middle child Dennis interrupted as he got the car boot open to help get the stuff out “Otherwise you know we run that call of the sea risk”. “Dennis” Your mother snapped over the statement. “Just telling them as it is mum” Dennis assured as your father joined in “After all you know Laura told me how she lost her older cousin to it two years ago”. “Didn’t need to be so blunt you know” your father pointed out.
What Dennis spoke about you recalled as being a famous risk of the place. How there was this pull in people’s minds whenever they were turned into merfolk. Was known to very from person to person but as Dennis said it was a call of sorts, a mental pestering insisting to remain a merperson. Most that hear it are usually indifferent but for the occasions one lacks the resistance or even before genuinely desire merhood of humanity end up refusing to return, a matter compounded by the fact transformations in either direction must be a willing process though thankfully at least most that choose to remain merfolk are hardly away forever from the coast.
You also recall Laura’s story yourself, how her cousin Alexis had come with her and her parents for a stay two years ago during a major nasty patch in Alexis’s parents’ relationship. You were never aware of the full details but Jessica once commented that it might have been a factor in Alexis choosing to be a permanent mermaid as opposed to returning, and that itself might suggest you’d likely be seeing her though under a new name as it wasn’t uncommon for those that choose to be merfolk permanently to change them.
Later that evening once everything was out of the car and in the summer house “So... who’s up for what to start this vacation?” your dad asked: