Charlize Theron has always wanted to adopt.

Charlize Theron

Charlize Theron

The 'Tully' actress - who adopted Jackson, now six, in 2012, and two-year-old August three years later - never planned to have biological children, largely due to her exposure to orphanages and children in need in the community where she grew up in South Africa.

Charlize - who has previously dated actors Stuart Townsend and Sean Penn - said: "Even when I was in relationships, I was always honest with my partners, that adoption was how my family would look one day.

"This was definitely not a second option for me. It was always my first."

And the 42-year-old star always knew she wanted more than one child, even though it's now meant having to deal with sibling rivalry.

She told People magazine: "We went through this really beautiful stage a year ago where the baby was hugging her sibling and there was all this love and affection.

"I was bawling my eyes out every day saying, 'This is the most beautiful love I have ever witnessed in my life.'

"Now the baby is almost three and realises she doesn't have to do everything her sibling tells her.

"There's a lot of wars in my house. I'm like, 'Where's the cute period that we went through?' "

The 'Atomic Blonde' star is a doting mother and doesn't even mind the sleepless nights she's going through at the moment.

She said: "My kids make me laugh like nobody's business.

"I'm kind of going through it right now because my little one is potty training, so night time, we're up three times a night changing sheets and pyjamas and things like that, but I wouldn't change it for anything."