The Hollywood couple - who are also parents to 11-year-old son Sasha - shocked fans by announcing their split in 2016 after 11 years together.
Since their break-up, the stars have been committed to co-parenting their boys and share equal custody to ensure their children were the number one priority, Daily Mail reports.
Speaking to US Sunday Today last year, Defiance star Liev admitted he was still coming to terms with the new arrangement but recognised the importance of maintaining a relationship with his ex for their kids' sake.
"It's always hard, you know? You build a life with someone and things change.
"I think the way that we've looked at it is that we'll always be partners with these kids. It's important to support each other.
"I was making some jokes at breakfast about Mommy with the boys and their eyes light up when I talk about her. You can see how important it is to them that their parents care about each other."