Who Was Niobe:
In Greek mythology, Niobe, who was the daughter of Tantalus, the queen of Thebes, and the wife of King Amphion, foolishly boasted that she was more fortunate than Leto (Latona, for the Romans), the mother of Artemis and Apollo, because she had more children than Leto. To pay for her boast, Apollo (or Apollo and Artemis) caused her to lose all of her 14 (or 12) children. In those versions where Artemis joins in the killing, she is responsible for the daughters and Apollo for the sons.
Burial of the Children:
In the Iliad, attributed to Homer, the children of Niobe, lying in their own blood, are unburied for nine days because Zeus turned the people of Thebes to stone. On the tenth day the gods buried them and Niobe resumed her life by eating once again.
This version of the story of Niobe differs from others in which Niobe herself turns into stone.
For some context, in the Iliad many lives are lost in efforts to recover bodies for proper burial. Disrespect of the corpse by the enemy adds to the loser's humiliation.
My Adaptation of Ovid's Story of Niobe:
Source: Ovid 6.146-312
Niobe and Arachne were friends, but despite the lesson Athena taught mortals about excessive pride -- when she turned Arachne into a spider, Niobe was inordinately proud of her husband and her children.
Tiresias' daughter, Manto, warned the people of Thebes, where Niobe's husband reigned, to honor Latona (the Greek form is Leto; mother of Apollo and Artemis/Diana), but Niobe told the Thebans they should honor her, instead of Latona. After all, Niobe pointed out proudly, it was her father who was accorded the singular honor for mortals of dining with the immortal gods; her grandfathers were Zeus and the titan Atlas; she had given birth to 14 children, half boys and half girls. In contrast, Latona was a vagrant who couldn't find a place to give birth, until rocky Delos finally had pity, and then, she had only a paltry two children. Niobe boasts that even if fortune takes one or two from her, she still has plenty left.
Latona is furious and calls her children to complain. Apollo shoots arrows (possibly of plague) at the boys, and so they all die. Niobe cries, but proudly says Latona is still the loser, since she still has more, with 7 children, her daughters, in mourning clothes beside their brothers. One of the girls bends to pull out an arrow and herself dies, and so does each of the others as they succumb to the plague delivered by Apollo. Finally seeing that she is the loser, Niobe sits motionless: the picture of grief, hard as a rock, yet crying. She is carried by a whirlwind to a mountaintop (Mt. Sipylus) where she remains a piece of marble with tears trickling.