Do You Remember That Night?

Choi Ae-ri and Park Seo-jin.
She loved him since kindergarten.
He never noticed her.
When he started dating a girl called Kim-soo in high school, Aeri realized that it was a one-sided love, and she became cold and stopped going after him, swallowing her feelings.
After a big betrayal and a fight, Aeri was the one who took care of Seojin, and that was the night when they slept together.
But unfortunately for Aeri, when he sleep-spoke his ex-name and when he woke up, didn't recognize her either and that was the cherry on top.
A week after that fateful night, Aeri got accepted to Harvard and started studying abroad.
Sometime after that, she discovered she was pregnant, with him, and kept that a secret from her family who knew his, but she decided to have the baby.
Now, eight years after that, she's famous abroad, and her son, Taeyoung is seven and a genius.
After an accident, she had to come back to South Korea with her son, having to face everything she left behind.
What is Seojin gonna do when he discovers that he has a son?
What is her family gonna do when they found out that Tae-Tae's father was closer than they ever thought?