Teddy had been watching the action unfold from inside a nearby cafe window. He hadn't been able to resist following. He knew Sirius was going to try to force the creature to assume the form of Bellatrix Lestrange, and he had the insane urge to finally come face to face with the woman who had killed his mother. If it wasn't for her, Teddy wouldn't have grown up an orphan.
Watching, Teddy saw the first jets of light begin to fly, but he could only see Sirius. He had barely missed a jinx and was now crouching behind a nearby car. Partly because he wanted to help his father's best friend, and partly because he had an insatiable need to actually see the attacker, Teddy crept to the cafe door and out into the street until he was crouched beside Sirius behind the car.
"Alright mate," he said with a forced grin. "Need a hand?"