NEW YORK: Weeds star Mary-Louise Parker had her sights set on adopting a child when she was just a little girl - she saw it as her duty to help out the world's poor.

The actress flew to Africa in 2007 and adopted a baby girl, named Caroline 'Ash' Aberash - a sister for her five-year-old son William, from her relationship with actor Billy Crudup.

The 44 year old admits she always knew she would open her home and her heart to an orphan as she set adoption as a goal early on in her life.

She tells People.com, "I would daydream about it all the time. I thought about the fact that there were children who didn't have anything, and I felt like I could help. It was something that weighed on me.

"It (adopting Aberash) was something I did for the world and for my son and then for me. And when I say the world, I also mean my daughter. Once I knew her, she became part of that."

However, single Parker confesses it's not easy juggling motherhood with her acting career.

She adds, "It's hard raising two kids as a single person, it's a lot of pressure."