Harry Potter and the Magic War
Book Four in the series begun with Harry's Future
This is the third installment , sequel to Harry's Future and Professor Potter, putting more emphasis on the adventures of the Potter and Weasley children.
A continuation from Harry's Future as Harry pursues the hopefully quiet life of a Hogwarts academic.
This is the first of several 'book's that form a fairly Canon bridge between the last chapter of Deathly Hallows and the Epilogue 19 years later.