Katniss holds Prim, encircling her little sister in the safety of her arms, and sings. Of a meadow. Of a better world where Prim can be safe and loved. The meadow, to Katniss, is beyond life; no place in their reality could offer such peace. Yet, years later, she somehow finds that meadow. Both in herself, and in the real world that surrounds her. Grown upon years of death and suffering, both Katniss and her home find life, even when she may have preferred death.
The epilogue of both the films and the novels is bittersweet, but it is filled with a kind of hope. There may never be a free happiness to be found for either Katniss or Peeta, who have suffered so much, but there’s something else for them: comfort, safety, the knowledge neither they nor their children will have to face those horrors again. They find a kind of peace.