Question: how is credence related to bellatrix?
Answer: Both Credence and Leta are the children of Corvus Lestrange by different mothers, making them half-siblings. ... As you might guess based on Leta's surname, she's an ancestor of the unpredictable and cruel Harry Potter antagonist Bellatrix Lestrange, and therefore to Bellatrix's cousins Sirius Black and Nymphadora Tonks.