Erelil’s grandmother Tirnel was a healer in the War of Wrath and one of the Vanyar. While in the war and caring for the sick and injured she eventually came to care for a soldier named Amathon. And even though her heart was filled with more and more love for him under the passing months from his honesty and thankfulness and smiles, she knew she could never stay when the time came to return to the Undying Lands. In part of the horrid things she’d seen the Enemy were capable of, and in part that she missed the light and warmth of the Valar.

But how could she ever leave him? The bliss she felt with him was akin to the one she felt in the presence of the Two Trees or the Valar, and yet it was completely different. She’d pushed it to the furthest corners of her mind as the war raged on, but once peace had come she made it clear that no matter how much her heart belonged to him she wouldn’t stay in a land which had been ravaged by dragon-fire and darkness.
However, their love for each other was too strong to ignore or break apart, which after some time resulted in pledged vows and the birth of a child, Malrin. When Tirnel still insisted on leaving for Valinor, Amathon persuaded her to stay, at least until their daughter was old enough to take care of herself.

The years went by and Malrin grew up to be very fair and joyous; Once she’d reached maturity in mind and body did Amathon and Tirnel tell her it was time to leave. But Marlin wouldn’t, for she had fallen in love with the starlight on the black sky and moonlit glades and the creeks who sang to her.
Tirnel became distraught, had it been a mistake to stay when she could have taken her daughter and went into the bliss of from whence she came? Why had Amathon insisted to stay? Yet, it would have been unthinkable to leave either of them.

Tirnel pleaded with her daughter, but Marlin wouldn’t listen for her spirit was still young and wanted to dance unseen by the shores and the trees, and only when she vowed to her mother to journey to the Grey Heavens and take a ship to her when she’d had enough of Arda did she reluctantly relent to her daughter’s wish. She then departed for The undying shores along with Amathon.

So Marlin stayed in Arda, and danced and sang along with the birds of the land. The years went by, and all the pain which touched the land went by her in a daze, as if she was in a dream. The carefree nature of her life would soon pass, however.
On one seemingly fated night, Marlin was dancing slowly in a field of beautiful flowers, dressed in simple shining white. Her voice lifted the still night air with high haunting tones.

Another elf, Calithilon of the Sindar, heard her signing, enraptured by the beautiful voice, he followed it until he came upon the fair Marlin and fell haplessly in love with her, and he took out his flute and started to play alongside her singing. Startled by the sudden sounds of music behind her, Marlin whirled around and the second she laid eyes on the dark-haired, fair form of Calithilon she too was struck by the deadly poison of love. He called her Ólwen, 'Dream-Maiden' for the time with her was like a waking dream.

The pair were then inseparable, and from their love a child came forth, just as it had sprung like a tiny seed into a flower for Marlin's own mother. They had a daughter who they named Erelil.

The familiy's happiness was shatttered when Calithilon went into the battle against the shadow of Sauron along with the other elves of Lothlorien who joined with the kings of men and the elves of Rivendell. He thankfully survived, but as he came home he noticed a change in his wife.

Her smiles were strained and harder to summon forth they they had been before, the light in her eyes he'd seen the night they meet seemed dim. And she rarely sang along with the sparrows or the other birds.

Marlin knew that now was the time to finally sail into the West, back into her mother's and father's arms and into the bliss of the Undying Lands. And so with a heavy heart she did, but not before she made Erelil swear the same vow her mother had made Marlin herself. Calithilon stayed behind to watch over his daughter until she in turn chose to sail westwards. Both of them live in Lothlorien.