Parentage:
She's the daughter of Eogabail, another name for The Dagda. Through him, she's the sister of Aengus and Brigid.
Consorts and Children:
In some stories, she is married to Gerald FitzGerald, Third Earl of Desmond, while in others, she's the wife of the sea god Manannán mac Lir.
Notable Stories Involving Her:
It is said that the King of Munster once tried to rape her, but she bit his ear off in retaliation. This resulted in his being declared unfit to be king, as an old Irish law dictated that only an unblemished person may rule. In this way, she's also associated with wealth and sovereignty, being able to grant or remove a king's right to rule. Midsummer is sacred to her, having been set aside as the night to feast in her honor.
Sacred Symbols:
Being that she's the goddess of summer and agriculture, the sun is a symbol of her, though she's sometimes also represented by a red mare.
Áine Around the World:
She's sometimes confused with the Celtic Anu/Danu.
SOURCES: Wikipedia, Encyclopedia Mythica, & GodChecker