The Australian model split from the 'Lord of the Rings' star last October after three years of marriage and she thinks separating was for the best for their three-year-old son Flynn.
Speaking on 'Good Morning America', she said: ''I think it's really important to have two happy parents. He's really happy and I'm happy.
''He's a great dad. I'm really lucky to have him in my life.''
The 30-year-old beauty also spoke about the pressure of body image after giving birth, insisting she readily accepted the fact her shape would change completely after carrying a child.
She said: ''I had to surrender completely to the fact that maybe my body would never get back into shape and I was fine with that.''
Orlando, 37, recently admitted he and Miranda, 30, felt it was important they continue to get along and ''respect'' one another for the sake of their son, and believes there will always be a ''deep love'' between them.
He said: ''It's ever evolving, but I've said to her, 'We're going to be in each other's lives for the rest of our lives and we have a child, so it's important to me that we respect each other as we always have and that Flynn feels that and understands that.' There's a deep love between us.''
'Wilson', starring both Dern and Harrelson, is released in U.S. cinemas on March 24th.
At just 13, Robert Irwin is continuing his father’s legacy and he’s just as enthusiastic about animals as his dad.
Madonna adopted twins Esther and Stella from Malawi earlier this month.