He passed her his badge so that she could feel the NCIS logo on the inside as a way to prove to her he was from NCIS like he said. "Well, then you know that I’m here to help you. Your daddy sent us. We know what happened to you and your mom, but you’re safe now, okay?" He lightly touched her arm that was wrapped around her knees to let her know where he was. Being blind, he wouldn’t be surprised if she heard him moving, but it was likely helpful to know exactly where someone was near you.