After Jin-tae and Ma-ri meet Jang-soo and Yoon-ja, they learn that Na-young is Su-ji's sister. Yoon-ja is ecstatic about Na-young's pregnancy, and Hyun-sung is shocked that Na-young and Su-ji are sisters. Su-ji plans to visit her parents after a long time, and Sun-young, who learns of this, calls Jang-soo to keep his mouth shut. Meanwhile, a heart-fluttering moment occurs when Doo-ri visits Do-young to nurse his summer cold.
