They met through Sydney's sister's Mother-in-law. Callie's Mother-in-law, Mrs. Donna goes to church with Casey. She chatted him up about Sydney and how she thought they would be great together. She told Casey all about Sydney, Callie, and their family. Mrs. Donna told Casey that Sydney was waiting for him to call her. One morning at work, Sydney received an instagram message, yes he slid in to her DMs. The twist? Sydney had never heard of Casey. Never seen him, never heard his name before, didn't even know he existed. After asking Callie about him, gotta be safe "stranger danger", she finally agreed to meet up with him. They met up face to face and the rest is history! Later on they discussed about how they met and how it was meant to be. Casey realized Sydney had not known about him before. He goes to tell Sydney he's so grateful it worked out, but honestly he's not that bold, he would never reach out to someone randomly who had never even heard from him. He had been under the impression, that Sydney had been waiting by the phone for him to message her.