Macaria

In Greek mythology, Macaria was one of the Heracleidae, children of Heracles.She was in Heracleidae, a play by Euripides. She and her brothers and sisters hid from Eursytheus in Athens, ruled by King Demophon. As Eurystheus prepared to attack, an oracle told Demophon that he would win if and only if a noble woman was sacrificed to Persephone. Macaria volunteered for the sacrifice and a spring was named the Macarian spring in her honor.
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[Greek] Macaria was the daughter of Heracles and appears in Euripides's play Heraclidae (The Children of Heracles). When she and her siblings took refuge from Eurystheus with Demophon, king of Athens, Eurystheus prepared to take them from the kingdom by force. Oracles told Demophon that his city would win the battle over Heracles's descendants only if a highborn maiden was offered as a sacrifice to Persephone. On hearing this, Macaria offered to die for her siblings. The spring where she died was named the Macarian spring in her honor.