When Teddy curled up in the corner of the sofa Sirius thought his heart would break. He knew Moony, he knew he must be feeling a million things and processing them all at once and turning to awkward rambling because that is what Moonys did. But it wasn't what Padfoots did, and it clearly wasn't what Teddy had been hoping for. Third wheel be dammed, he was going to make this a touching family reunion if it killed him.
He grabbed Remus by the hand and physically dragged him over to the sofa where Teddy looked so small and alone. He plunked Remus down on one side of Teddy and put himself on the other, sandwiching him in and throwing his arms around him like a clingy spider monkey. He gave Remus a very significant look, which all but shouted hug him! Hug him now! He thinks you don't like him!