Good Luck in the Year of the Pig

In short: an old lover gave me a little piglet.
Qin Zhuopu, a workaholic, has been single for many years. As he reaches middle age, his family is desperate for a child.
Until one day…
“Mr. Qin, your son is already in primary school!”
“???” I have only had one boyfriend!
Seven years after the breakup, the old lover returned to the wealthy family with a little fat pig in his arms: “Zaizai is a big eater, I can’t feed him. Zaizai’s primary school homework is too difficult, I can’t do it. I’ll give you guardianship from now on! Will you let me go to your construction site to move bricks? Son, say ‘Mommy’!”
Mr. Qin: (No, I couldn’t give birth to such a fat kid!)
Later…
Onlookers: I heard that Mr. Qin has adopted an illegitimate child born to his old lover by some woman?
Mr. Qin: Let me introduce to you, this is my own cub!