The Older Brother of My Student is My Secret Crush - Chapter 13: The Missing.

Seven years ago, Shen Qianshu is impregnated with Ye Ling’s child in an accident.
Seven years later, the little boy becomes famous and is thought of as the nation’s son.

When he suddenly sees Ye Ling appear, he greets, “Hello, Daddy?”
Ye Ling watches as the little prince roars, “Where’s my princess?”
Just as Shen Qianshu is preparing to run with her son, she gets pushed down by Ye Ling.

“You can leave if you want, but leave me a princess first. Let’s have another baby!”

- Description from Novelupdates

He swore that if he was given a second chance to live, he would live his life to the fullest.His life was full of misery but he was reincarnated in the body of the son of the strongest expert in the empire.He had the looks, wealth, and women. He was known as the “Handsome Playboy” and he didn't want to become a righteous protagonist.He awakened a system that can make him strong by making others feel the 7 sins towards him.He will collect many beauties and live to the peak of life.

Tian Han was a young boy who admired immortals. His dream had always been to become like them—flying on swords, using spells. But he was just an ordinary village boy, and he didn't have much of a chance for that. So, he always read books about immortals, and his admiration for them grew more and more every day. One day, he heard that he had a chance to become an immortal.“You can become immortal.”This was the sentence where his adventure began. Yes, he could become an immortal. And so, his journey started, and he found himself in the ruthless world of immortals.