1. Listen patiently: First of all, you need to listen patiently to your mother's complaints and dissatisfaction, understand her feelings, and express your understanding and support to ease her emotions.
2. Clarify the principle of role assignment: It can explain the principle of role assignment of actors, the selection criteria of actors, and Chen Chen's performance, advantages and disadvantages, etc. Let her know that Chen Chen didn't get the role she wanted not because of her poor performance, but because of the objective criteria and constraints of actor selection.
3. Find a way: You can find a way with your mother, such as helping Chen Chen find other more suitable roles and providing professional actor training to improve Chen Chen's acting level and role competitiveness, thus increasing her chances of getting the ideal role.