The LOVE ACTUALLY star, who was devastated when In Vitro Fertilization (IVF) treatment failed to help her provide a brother or sister for her six-year-old daughter GAIA, decided to adopt TINDYEBWA AGABA after doing charity work in war-torn Africa.
She says, "IVF is horrible, and all those drugs and the invasiveness of it.
"I started to think about the things I could do usefully to help children.
"Funnily enough, through finding something else to do with my mothering instincts, other children have come and there is something to offer them - a life with an extended family, which I think is preferable to an entirely nuclear family.
"Tindyebwa is doing brilliantly now. He got wonderful A' Level (exam) results this summer.
"He's putting in applications for university. He's going great guns."
Agaba's parents were both killed during the Rwanda civil war.