Su Yan had said that to stop Su Zheng. She didn't want Su Zheng to go over and argue with Su Qing now, or her lies would be exposed!
The best way was to let Su Zheng build up his dissatisfaction and disgust towards Su Qing. When Su Zheng was unable to tolerate it anymore, it would probably be impossible for Su Qing to remain in the Su family again.
However, when Su Yan saw Su Zheng's serious expression, she had another idea. She suggested to Su Zheng, "Daddy, didn't Grandma used to have a helper who can do etiquette training? We can ask Grandma to loan her to us!"
"You mean Auntie Liu from the old mansion?" Su Zheng asked uncertainly.
Su Yan nodded. "Auntie Liu has been with Grandma for a long time. She would know how to teach Su Qing manners. When I met her once in the past, I already felt that Auntie Liu was very capable! If she could teach Su Qing, you wouldn't have to worry anymore!"