The War in Heaven had always been a sore spot for Selûne.
As mentioned earlier, after the Overgod Ao created the Realms, Selûne and Shar were born from chaos. The two goddesses initially lived in harmony, but things changed with the birth of the third deity, the Earth Mother Chauntea.
Chauntea represented the primary material planet of the Realms itself, but the endless void and darkness meant endless cold. Unable to bear it, she asked the two goddesses to grant her warmth and light.
Selûne heard Chauntea's plea and brought a "seed" from the Elemental Plane of Fire. Thus, the sun was born.
The tranquility was shattered, and Shar was furious. What the goddess of night loved most was the darkness and stillness of the endless void. With the sun's appearance, however, light entered the Realms, and as the land filled with life, the creatures born upon it made a noisy racket.
That was the cause of the War in Heaven-Shar wanted the Realms to return to their former cold and stillness.
The War in Heaven ended in a narrow victory for Selûne. Defeated, Shar could only accept what had already happened and retreat into the darkness, constantly searching for an opportunity to make a comeback. Those events had already been covered, so there was no need to repeat them here.
Mama Selûne understood what Aaron meant.
Countless ages had passed since the War in Heaven, yet the two goddesses had profoundly different attitudes toward it. Shar never stopped plotting to destroy her sister and all living creatures, returning the Realms to their former darkness and nothingness. Selûne, by contrast, had no plan to destroy Shar completely.
When it came to her sister, Selûne mostly defended herself and counterattacked. She unraveled Shar's schemes against her one by one, punished mortals