Lily was born to two Muggles, and was the younger sister of Petunia Evans The two often spent time together, doing such things as riding the swings, although Petunia was often annoyed by Lily's blatant use of magic. One such instance was in the summer of 1971, when she and her sister first met Severus Snape. Although her sister was reluctant to accept Snape, she soon became his friend after he explained that she was a witch, and he in turn explained the basic facts of the wizarding world.