In a quiet cove on the northern coast lived two mermaids unlike any others: Sorella and Niva, the Tide-Glass Sisters. Their tails shimmered like frosted quartz, clear as water but lit from within by soft colours that shifted with their moods — rose for joy, storm-grey for anger, deep emerald for sorrow.

Legend said they were born from a single tear dropped by the Moon into the sea. Whether or not that was true, the sisters were inseparable.

The cove they lived in held a secret: a pool tucked under an arch of rock, so still and bright that even the fish swam around its edges in reverent circles. This was the Mirror Pool, a place where mermaids could see moments from the past — not all moments, just the ones the sea itself remembered.

Most mermaids used the pool only for stories or songs. But the Tide-Glass Sisters had another reason.

Years ago, their mother — Mariane, a fierce mermaid-warrior with coral armour and hair like drifting silver — had vanished while protecting their home from hunters. No body was ever found. No trace. Just an empty space in the currents where her presence used to be.

Sorella believed their mother lived still. Niva believed she was gone. Both felt the ache of not knowing.

One evening, when the water glowed gold and the horizon looked like molten metal, the Mirror Pool flickered. Just once. Like a heartbeat.

The sisters rushed to it.

A shimmer rose on the surface, forming a blurred vision: a mermaid trapped in a maze of kelp, struggling weakly. The image was fleeting, but the flash of silver hair was unmistakable.

Mariane.

Sorella didn’t hesitate. “We can find her.”

Niva hesitated, fear knotting in her chest. “What if it’s a memory? Not now… but then?”

But the Mirror Pool had never shown a memory with such urgency. The water felt alive under their fingers, tugging them, guiding them.

So they went.

The maze lay far to the west, where currents snarled and light failed. The kelp there grew thick and tall, ropes of it twisting around ancient anchors and ship ribs. No merfolk swam there if they could help it — too many things lurked in the murk.

Inside the maze, the sisters sang to each other to stay close. Their tails glowed bright to keep the gloom back.

At the heart of the labyrinth they found her.

Mariane, wrapped in kelp that held her like iron bands. Alive — barely — but fading fast. The kelp was no ordinary growth; it moved, tightening when Sorella tried to cut it. It was a guardian plant, awakened long ago to protect the ruins beneath.

But Niva noticed something: when they held hands, their colours pulsed together, stronger. Clearer.

Their shared glow spread across the kelp. The strands quivered, loosened, then fell limp — soothed, not fought.

Slowly, gently, the sisters pulled their mother free.

Mariane breathed — a long, shaky pull of water into her gills — and opened her eyes. Recognition shone there, soft as moonlight.

“My girls,” she said, voice weak but steady. “You came.”

Sorella laughed through tears. “We always would.”

Niva held her close. “We’re whole again.”

The return journey was slow, but by the time they reached the cove, Mariane’s strength had begun to return. The Mirror Pool was waiting, its surface calm and shining.

For the first time in years, the three of them looked into it together — and the pool showed not the past, but the present: three mermaids, glowing in one shared light.

The Tide-Glass Sisters finally had their answer. Their mother hadn’t been lost — only waiting for them to come as one.

And from then on, when the pool flickered, the merfolk of the cove didn’t fear it. They said the sea was whispering, guiding, remembering.

And the Tide-Glass Sisters listened.