Aglaulus

Aglaulus is the name of three figures in Greek mythology.1. Aglaulus, daughter of  Actaeus, king of Athens. She married  Cecrops and became the mother of Erysichthon, Aglaulus (see below), Herse, and Pandrosus.2. Aglaulus, daughter of  Cecrops and the Aglaulus listed above. According to Apollodorus, Hephaestus attempted to rape Athena but was unsuccessful. His semen fell on the ground, impregnating Gaia. Gaia didn't want the infant Erichthonius, so she gave the baby to Athena. Athena gave three sisters--Herse, Pandrosus and Aglaulus--the baby in a small box and warned them to never open it. Aglaulus and Herse opened the box which contained the infant future king, Erichthonius. The sight caused Herse and Aglaulus to go insane and they threw themselves off the Acropolis. According to Pausanias, she is the daughter of Actaeus.
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[Greek] In Greek mythology, the daughter of Cecrops, sister of Herse and Pandrosus. When the city of Athens was once under siege for a very long time, Aglaulus voluntarily hurled herself from the Acropolis, because an oracle had spoken that through such a sacrifice the city would be saved. In her temple young Athenian men who were called for service made the oath to guard their fatherland. According to other sources, the goddess Athena had entrusted the three sisters a small box that was not to be opened under any circumstance; the young hero Erichthonius had been laid inside the box. When Aglaulus and Herse opened the box and looked upon the face of the child, they were stricken with madness, and hurled themselves from the Acropolis.