|Equuleus is the ancient designation for this small constellation. Even Claudius Ptolemy included it on his maps as the little horse. It's the second smallest constellation, the record for smallest being held by the southern cross. It's usually drawn as just a horses head, sometimes peaking out from behind Pegasus. Maybe they're related, on the non-winged side of the family.
The back-story is sketchy but there is a Greek version where a centaur's free-love daughter named Hippe was guilty of accidentally "getting pregnant without permission." To help her avoid punishment, The moon (Diana) turned her into a little horse. Then she found Pegasus and asked for help hiding her in the mountains.
The love-child's absent father is reportedly Aeolus, which is The Wind and you know how unreliable he is. Blows into town, blows out. The baby, Melanippe, is born from the wind and a horse, but she isn't a constellation or anything.
Hippe raised young Melanippe up in the mountains, probably with a dog named Zippe.
Equuleus has no bright stars, no bright deep sky objects, and no meteor showers. The Chinese call it the "Wise Black Tortoise of the North" which would make more sense if there was also a foolish white tortoise of the south. Sadly, there is not. There is however the Wealthy Azure Dragon of the East, the Powerful White Tiger of the West, and the Lucky Vermillion Bird of the South. If you want my advice, I would avoid the Smelly Green Egg Roll of Regret.