Katherine Heigl is "surprised" her husband is such a "great dad".

The 31-year-old actress - who has a 22-month-old adopted daughter Naleigh with her spouse Josh Kelley - felt confident she would be able to adapt to motherhood but wasn't prepared for how well the musician would cope with being responsible for someone else.

Katherine said: "He's a great dad. I didn't expect it.

"He's such a guy. I adore him, I can't imagine being with another man, but he can be very self-absorbed. Not in an egomaniacal way, just kind of in his own head and unfocused on anything other than his own stuff. So I was really surprised by how on top of it and how connected he is."

The brunette beauty - who adopted Naleigh from South Korea, the same country where her older sister Meg was adopted from - also revealed she and Josh would consider giving a home to another disadvantaged youngster

She told Redbook magazine: "We still talk about having biological children as well. I'm not ruling anything out.

"Adoption has been a part of my life and a part of my family, so it was how I wanted to start."

Katherine and Josh were awarded legal guardianship of Naleigh just days before the actress was due to start filming new movie 'Life As We Know It' and she admits she initially struggled to juggle her commitments.

She explained: "I had just become a mom. I was all over the place. I was really trying too hard. I was completely bonkers.

"If I spread myself too thin. I'm not a good actor, I'm not a good mother, and I'm just really highly strung - and everybody hates me."