When Voldemort murdered the Potters, a grieving Snape vowed to protect Lily's child, although he loathed young Harry for being James Potter's son.
Kui Voldemort tappis Potterid, siis kurvastav Snape tõotas kaitsta Lily last, kuigi ta jälestas noort Harryt sellepärast, et ta oli James Potteri poeg.