Hayden Panettiere is concerned her daughter is experiencing "trauma" as a result of their separation.
The former 'Heroes' star lost custody of seven-year-old Kaya when the youngster was almost three years old so the tot lives with her dad, Wladimir Klitschko, in Ukraine, and the 33-year-old actress was left horrified by a conversation with her former partner when he told her their child kept asking to call other women "Mommy".
Speaking on 'Red Table Talk', Hayden said: "I also remember her dad [Klitschko] calling me and telling me Kaya's going around and asking other women if she can call them mommy.
"My breath hitched and my heart stopped, and he was laughing. He thought this was funny and it was horrifying to me.
"He didn't get it as opposed to me who saw that's a trauma reaction. That's a cry for help.
"I said immediately can I talk to my daughter, and when I asked her about it she went into goo-goo ga-ga speak, like just talking gibberish. I never before heard her do that.
"It was a trauma that she was experiencing, me not being around."
Hayden suggested Wladimir "doesn't understand" the lasting impact on Kaya.
She added: "As much as I have tried to explain how much she needs her mom and how it's going to rear its ugly head when she's older later and it could turn into anger, depression, sadness, but it's going to be trauma. You can explain it to someone who doesn't understand that concept or believe it until you're blue in the face."
The 'Nashville' actress - who has been candid about her struggles with addiction and depression - praised Kaya as an "incredibly strong child".
She said: "She's a very stoic child. When she really gets hurt, you can see her try to hold it back, really hold it in and be like 'I'm fine,' and dust it off and not want to be held."
The blonde beauty found the way the decision about custody of Kaya was made was "very upsetting".
Co-host Adrienne Banfield Norris asked: "You thought this was an agreement that you came to that it was best that your daughter be with her dad?"
Hayden replied: "At first it was not because it wasn't a discussion.
"If [Klitschko] had come to me and said I think because of where you're at right now and your struggles that you're having it would be good for her to be over here with me for a while — which if I had probably had enough of a conversation I would've said okay that makes sense, I get it, I'll come there to visit and stuff like that.
"I was gonna go work on myself, I was gonna get better, and when I got better then things would change and she could come to me and I could have my time with her but that didn't happen."