Heliades in Wikipedia

In Greek mythology, the Heliades ("children of the sun") were the daughters of Helios, the god who drove the sun before Apollo. According to one source, there were three: Aegiale, Aegle, and Aetheria. According to another source, there were five: Helia, Merope, Phoebe, Aetheria, and Dioxippe. The fourth or sixth Heliades was a son called Helias. Their possible brother, Phaeton, died after attempting to drive his father's chariot (the sun) across the sky. He was unable to control the horses and fell to his death. The Heliades grieved for four months and the gods turned them into poplar trees and their tears into amber. According to some sources, their tears (amber) fell into the river Eridanos. According to Hyginus, the heliades were turned to poplar trees because they yoked the chariot for their brother without their father helios' permission.[1] - Wikipedia