Trouble with my husband

Hello coaches,
I’ve been having a hard time in my relationship with my husband for a few years. We’re a step family. His daughter doesn’t want to come to our house anymore. He’s sad and doesn’t want to be closer to his step children than he is to his daughter.
He gives orders and yells at my two children very often (because they do or don’t do this or that). My children think he’s grumpy. Whenever he behaves like this, I get mad at him, anxious (because I’m afraid my children won’t be happy to live with me anymore), and frustrated (because the situation keeps repeating itself over and over). We end up arguing and it doesn’t change anything.
I don’t know how to deal with the situation. I really don’t know what thought could make me feel better. Could you please help me?
Thank you very much.