"Mother, where is father going? He was just behind us"
Draco couldn't see is father in the middle of the confusion of that battle. He didn't know if he was well. Since the last time he saw his father, his eyes are sadder like a shadow as pass through him and take all the happiness in the world.
Lucius was now on his way to the boathouse. He had to see Severus, he had to see what Voldemort has done to him. He had to see the face of the only person he trusted and loved as his family, the one with whom he had divided his love all these years, even if he know that Severus was never his. Severus always loved Lily, he only played along with that relationship with Lucius because he didn't have no one else in his life, and Lucius knew his secret, we knew he as a halfblood, he knew he decided to keep Harry safe. And he had kept that secret his entire life.
"Severus…" was the only word Lucius could say in that moment before his tears started running over his face. Carefully he put his hand on Severus hair and whispered.
"Thank you Severus, thank you for saving Draco, for saving my family, for everything you ever done. One more time I will say I love you without a response, but I guess right now you can finally see her again."