The actor's mother, Choi Soo Min, was the voice actress of famous cartoon characters like a Smurf and Young Shim. While watching some of the cartoons with Choi Soo Min's voice, Cha Tae Hyun failed to recognize her, and commented, "It doesn't sound like my mom. Did the producers find the wrong ones?"
However, after paying closer attention, Cha Tae Hyun stated, "It is my mom. This voice is such an older voice of her. Her voice in 1983 is unfamiliar to me."