"Dannielynn knows that her mom passed away. She obviously doesn't know the details," he tells Us. "At first I said, 'Your mommmy's up in the clouds.' Then we were on a plane from Kentucky and she asked, 'Which cloud is my mom on. Maybe she can come play?' You have to be forthright but keep it on a kid-friendly level."
Still, life as a single parent hasn't been easy for Birkhead, 38, who was granted custody of Dannielynn in April 2007 after a dramatic paternity suit with Smith's partner Howard K. Stern.
"It's hard to flip from friend to parent. I overcompensate because she doesn't have a mom and I probably give her more than I should," he tells Us. "I'm working on cutting down on the shopping sprees."
For more on Birkhead and Dannielynn's life without Smith — including how they plan to spend Father's Day together — pick up the new issue of Us Weekly, on stands now.
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