Marry a Hidden Boss, Find My Daughter

Stephanie is back in the country with her son, looking for her daughter, who was taken from her years ago. She has been away five years. A mix-up puts her into a sham marriage with Lysander, a single father who runs the Lu Group and keeps that to himself, and the two of them agree to the arrangement for their children's sake. The children have their own plans for it. Her son and his daughter work at pushing the two adults together, and it starts to take, while Stephanie and Lysander deal with schemes inside the family and with people working against them from out of sight. Lysander's daughter carries the same birthmark as the child Stephanie lost, and in time it comes out that she is that child. Once Stephanie and Lysander know it they go after the people behind the taking and the plotting, and look after each other and the children while they do it.