Once a litlle lamb was grazing in the field when suddenly Slyph, the goddess of everything in the ancient civillization of the Sanous, floated down to the lamb.
She said 'You are a kind and honest creature, may you live forever'.
Then she disapeared.
As she said so the lamb never grew old, once a decade it would change shape to another baby creature such as a foal or piglet. It is said that Layla the lamb still lives today but who knows?