As the Titan Protector of the Young, Leto was the "world's first babysitter", and therefore popular with all the Titans since she would help them babysit their children.
Zeus came to fall in love with Leto, and charmed her into having an affair with him, which concluded with her becoming pregnant with twins (Apollo and Artemis). When Hera found out, she cast a curse: no land with roots in the earth could receive Leto when it was time for her to give birth, and yet Leto could only give birth on land. Due to this curse, Leto was driven from land to land, but unable to find a place to rest and give birth. She also caught the attention of Python while trying to consult the Oracle of Delphi for advice, and barely escaped with her life.
Through her children, Leto came to establish a reputation that she was a personage to be treated with all reverence, for no one could behave inappropriately towards her without incurring the wrath of her children: once, when she was traveling to Delphi to visit her son, the giant Tityos attempted to abduct her, but Apollo intervened and slew him with arrows, and even ensured that Tityos' soul was tormented for all eternity as punishment. The second instance was when Niobe, the Queen of Thebes, slighted Leto by claiming that she was better than the Titaness, for she had fourteen children (seven sons and seven daughters) while Leto only had two. To punish Niobe, an indignant Apollo and Artemis slew all of Niobe's children.
Latona is Leto's Roman counterpart. As Latona, she becomes more disciplined, warlike, and militaristic. In Roman mythology, she is the Titaness of Motherhood and Modesty.
Leto was mentioned by her father, Koios, to Iapetus in Tartarus. He claimed that his daughter would likely fight for vengeance alongside the Titans after the way Zeus treated her even after she bore him two twins. It is implied in the same book that Leto was forced to reform at some point, as her father Koios stated that peaceful titans take longer to reform, hence why Iapetus hadn't seen her in a very long time. The exact reason, point in time, or ramifications of this are not clear.
Her son Apollo mentions her frequently throughout the book. He also recalls that she used to call him 'a special snowflake'.
After Apollo drinks from the two springs of memory and forgetfulness to prepare for his trip into the cave of the Dark Oracle, he begins hallucinating, and one of his visions is of Leto kneeling and pleading with Zeus to end Apollo's punishment and allow him to return to Olympus. However, Zeus refuses, saying that his real test is yet to come.
In The Dark Prophecy, Leto was described to have long golden hair that zigzagged down her back in an elaborate ladder weave, and bronze arms that glowed against her white sundress.
- Photokinesis: Leto is often known as a goddess of light, something inherited by her children so it is likely she posses this ability though to a lesser degree then her children.
- Archery: Leto's children, her brother Lelantos and niece Aura were all known for their archery skills so it is likely that she possesses some skill in this area though to a lesser degree than her children.
- Motherhood - As the Titaness of Motherhood, it is implied that she bears influence over children and procreation. She may share some powers with Hera in this sense, and it could also explain why her children are some of the strongest of Zeus' children. She may also posses some influence over maternal and domestic duties such as raising children, easing pain, calming children, cooking, cleaning and other tasks connected with the idea of motherhood in Ancient Greece.
- While not an outright power, Leto is slow to recover due to her peaceful nature.