We're Already Married

"Our whole lives we have always told people that we were married. I knew that it wasn't exactly normal but it was always something that filled me with so much affection for you. I have loved you for so long. Longer than I ever realized." Harry took a deep breath as he looked into shining silver eyes.

Or...

Three-year-old Harry asks little Draco to marry him and they insist to anyone who will listen that they are indeed already married.