Fantastic Beasts and Where To Find Them was initially introduced to fans as a trilogy of movies about an entirely new character, in a different era, introducing new corners of the Wizarding World never seen before. But by the time Fantastic Beasts: The Crimes of Grindelwald rolled around, the tiebacks to the Harry Potter series were everywhere. From Dumbledore to Nagini, it seems like nearly every character ties back to the Potter books, save one: Newt Scamander. But will that remain the case? Are Newt Scamander and Harry Potter related?
Unless J.K. Rowling really pulls a number on her world build, the answer continues to remain no. Though the Scamander family trace their heritage back several generations, they are not part of what's known as the "Sacred 28," which are wizarding families who the Pure-Blood Directory claimed as the last families to be untainted by Muggle inbreeding during Grindelwald's rise in the 1930s.
Instead, they are a modest family, mostly comprised of Hufflepuffs and Gryffindors, who spend their days working with magical creatures and fantastic beasts, in the field of magizoology. During Harry's time at Hogwarts, Rolf Scamander, sorted over into Hufflepuff, was also a student. He married Luna Lovegood after the Second Wizarding War.
The Potters, meanwhile, trace their heritage back farther than most, descending from Ignotus Peverell and Linfred of Stinchcombe. Their family actually should have been including in the Pure-Blood Directory when it was publishing in the 1930s, but their egalitarian attitudes towards intermarrying with Muggles made author Cantankerus Nott suspicious of their bonafides, so he excluded them from the list, something the family wore with pride at the time.
There was also Linfred of Stinchcombe's habit of intermingling with Muggles, considered "a corrupting influence" down the family line. Known as "The Potterer" (hence the origins of their last name), most muggles thought him and his herbal cures harmless if a trifle eccentric. But Linfred was a resourceful chap and invented several remedies still in use to this day, including Skele-Gro. Obviously, this taste for potions puts the Potter family in the company of other Hufflepuffs like the Scamander family. But as far as the history books are concerned, they are not related.
Of course, this doesn't mean Rowling couldn't change this if she wanted. The fact is, the Potter family tree is not fully fleshed out the way some others in the canon have been. And though the Scamander family goes back a way, there's no "first Scamander wizard" story to anchor them the way Ignotus Peverell does for the Potters.
Rowling's need to find ways to tie her two franchises together may yet drive her to invent a way the Scamander and the Potter family trees intersect. Knowing her, she'd set it somewhere in the distant past, long forgotten in the here and now. After all, if there's one thing the Wizarding World is teaching us in the new franchise, it's those who live in it are far more connected than anyone ever realized until now.