Question: how does snape have lily's patronus?
Answer: Severus Snape's Patronus was also a doe, which symbolized his love for Lily. Snape uses his doe Patronus to show Dumbledore that he never fell out of love with Lily, his childhood best friend. ... According to Rowling, Snape was the only Death Eater who could conjure a Patronus charm at all.