The magical world of Harry Potter is as complex as it is fascinating. And that goes doubly so for family ties. Thankfully, we know a fair bit about the genealogy in this world. And yet there are still surprises to be found – or to be reminded of.

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The pureblooded wizarding families all seem to be connected, but that makes total sense when you think about it. After all, there are only so many families you can marry into if you want to maintain that status. So it’s really no surprise that Sirius is related to so many different characters. And yet it’s not something we frequently think about. So with that in mind, here are ten of the most surprising relatives to Sirius Black.

10. Bellatrix Lestrange

Bellatrix Lestrange in Harry Potter.

Bellatrix Lestrange is perhaps one of the first names that come to mind, when one tries to remember all of the people that Sirius is related to. She's certainly the most iconic and one of those characters that everyone just loves to hate.

And you can probably understand why Sirius would have simply been happier if everyone just forgot that he was related to somebody like her. And it's really only adding insult to injury, given the part she had to play with his death.

9. Millicent Bulstrode

Do you remember Millicent Bulstrode? She's not a character mentioned overly much in the world of Harry Potter – and with good reason. She did, however, play an important role during the second Harry Potter novel. She was the girl that Hermione was going to try and turn into, using the Polyjuice potion. And everyone remembers how well that worked out.

Well, anyway, you might be surprised to hear that Sirius was related to that little witch. They're not close relations, by any means. But the blood tie remains regardless. One of Millicent's ancestors, Violetta Bulstrode, married into the Black family (Cygnus Black III), and the rest was history.

8. Vincent Crabbe

Vincent Crabbe

While we're talking about minor characters from Slytherin House, let's talk about Vincent Crabbe. He was one of two goons essentially assigned to hang out with Draco Malfoy, and that implies something about his blood status.

And that means that he also is related to Sirius. Though once again, Sirius would probably prefer that this connection to the Crabbes didn't exist. They're both related through Irma Crabbe, who married Pollux Black (Sirius' grandfather).

7. Draco Malfoy

Malfot at Hogwarts looking serious in Half-Blood Prince.

Draco Malfoy should probably be another obvious connection in this twisted family tree. After all, if Bellatrix is related to Sirius, then that logically means that Draco is as well. And yet that's a fact that we all often seem to overlook.

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Draco's mother is Narcissa Black, which makes Draco Sirius' second cousin. So once again we find this family tree getting just a bit more complex and twisted. Thankfully this is a connection that Harry failed to notice, at least to our knowledge.

6. Marcus Flint

Marcus Flint and Angelina Johnson playing Quidditch

Go ahead and add Marcus Flint to the list of Slytherin characters that Sirius is related to. You noticing a trend yet? Because you probably should. A lot of the families headed towards the Slytherin house cared about bloodlines, and there are only so many families to marry into, which has some consequences.

Such as having Marcus Flint as a distant relative. Granted, in this case, the relation is quite distant, with Sirius' great-grandfather being the closest connection between the two. But still, not ideal.

5. Barty Crouch Jr.

David Tennant in Harry Potter looks off camera.

The Crouchs are yet another family line that once became entangled with the Black family. It seems like basically every pureblooded family has married into or out of the Blacks at one point in time.

And that means that Barty Crouch Jr. is related to Sirius Black. Once again, the connection is not a close one, with their great-uncles being the only direct tie back towards one another. But it's still too close to comfort for many.

4. Yaxley

While we're talking about people we hate to think about being related to Sirius, let's talk about Corban Yaxley. Yaxley is a Death Eater that fans saw again and again during Harry's fight against Voldemort's rise. He later became the head of the Department of Magical Law Enforcement, when Voldemort came into full power.

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And he's also related to Sirius, sadly. Once again, we imagine that this is a relation that Sirius chose to ignore. And who can blame him? This is the same family brach that wound up becoming related to the Crouchs, Prewetts, and Longbottoms (more on those in a moment).

3. Neville Longbottom

There are some good connections to be found, in this twisted family line that Sirius was forced to bear. For example, did you know that Sirius is actually related to Neville Longbottom? Yes! It may be hard to believe, but that is exactly the case. Though we imagine the Blacks were not pleased with Neville's parents and their joining of the Order of the Phoenix.

Neville's great-grandmother was Calidora Black. Which means that Neville has some of their blood running in his veins. His ties back to Sirius are slightly thinner, but it's still not something that can be denied.

2. Arthur and Molly Weasley

Moly and Arthur stanging in a doorway in Harry Potter

Did you know that both Arthur and Molly Weasley are related to Sirius Black? And no, we don't mean related by marriage. Each one of them has ties back to the Black family. Remember that nearly every pureblooded family left has connections to the Blacks, and it makes a bit more sense.

Arthur Weasley's mother was Cedrella Black, and thus his tie to the Black family is a bit stronger than his wife's. Meanwhile, Molly had an aunt by the name of Lucretia Black. These connections eventually are what make Harry related to Sirius as well, so that's fun food for thought.

1. Nymphadora Tonks

Tonks looking at the camera in Harry Potter

And finally, would you believe that Nymphadora Tonks is related to Sirius Black? It's true! In fact, this whole complicated family line is the reason why Tonks was hunted so fiercely by Bellatrix (due to Tonks marrying Lupin).

Tonk's mom is Andromeda Black, and she's the sister to Narcissa and Bellatrix, as hard as that might be to believe. And that means, by blood, that Tonks and Sirius are also related. Just with a bit more distance.

Fun fact! That also means that in the end, Lupin and Sirius were related to one another by marriage (though sadly Sirius never lived to see that day).

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