What was the complained of Cinderella to her step mother?

Cinderella did not complain to her stepmother. In the story, Cinderella was treated poorly by her stepmother and stepsisters, but she never complained or fought back. She endured their cruelty and mistreatment with patience and resilience.

It's important to remember that Cinderella's story is a fairy tale, and the focus is on her goodness and kindness, even in the face of adversity.