The Cursed Child is Rita Skeeter's latest "exposé" and she's missed the Big Scoop: Delphini's Pregnant! Probably. It's taking a while to check. Lots of original characters but I'm trying to follow canon except Parselmouth Harry. That's going to have nothing to do with Harry the Horcrux. Not sure what sort of tone this going to end up with. Dramedy maybe?

After the Epilogue, Dudley and his wife are surprised to find themselves pregnant again. Twenty years later, that daughter is surprised to find herself pregnant. Then, in 2049, sixty-nine year old Dudley is surprised to find his eleven year old granddaughter has a letter. But how to explain that it's real? Characters are all from, or descended from, J K Rowling's Harry Potter.