3 yr old having recurrent nightmares

My husband and I split up 9 months ago. He was very verbally abusive, emotionally abusive, would destroy our home over small arguments, etc. he never put his hands on any of us though. My 3 year old has had a few nightmares (began the week before we left after a traumatic event with dad) and each time when she wakes up and I ask about the nightmare she just cries and says daddy. Tonight she has had 4 nightmares so far (she’s had several this week, following a visit with her dad that was supervised by me last week) and a few minutes ago had one so bad that she was screaming “NO! NO! NO!” Then said “I want my mommy” I comfort her every time of course but I don’t know what else to do and also don’t know how concerning this should be. I’m very worried. I haven’t always been the one to supervise and I suspect that his sister didn’t supervise as well as she led on. Our younger baby has gotten hurt many times in his care. I’m worried that he has done something since the first event that has further traumatized her. I called a couple days ago and got her enrolled in therapy and I’m hoping I can get some answers. I don’t know what else to do.

Ps. When I ask her about what happens in the dreams she won’t tell me/describe them. Only says daddy.