Question: are draco and sirius related?
Answer: He marries Narcissa Black and together they have one son, Draco, who is the first Malfoy family member introduced in the series. The Malfoys are related to the Black family through Narcissa (a first cousin of Sirius Black, Harry's godfather), which makes Draco a nephew of both Bellatrix Lestrange and Andromeda Tonks.