Reese Witherspoon says any form of domestic violence is "absolutely unacceptable".

The actress is educating her children Ava, 12, and Deacon, eight, about physical abuse and has spoken to them about Chris Brown's attack on Rihanna.

The 2009 assault has been making headlines recently as the pair are rumoured to have reunited.

As the Global Ambassador for the Avon Foundation for Women, Reese is clued up on the matter and is adamant to spread the word against violence.

"My daughter knows what happened [to Rihanna]. My son knows as well," she told People. "We talk about what is abuse. I think it's important to talk to our daughters and our sons in order to educate them at an early age about what's appropriate and what is absolutely not acceptable."

Reese added that while her children have grown up in a happy home, they are aware that domestic violence is an issue that is affecting families all over the world.

The blonde beauty explained that as a mother, it is her responsibility to educate her kids on difficult issues.

"Although the concept is somewhat foreign to them, they're starting to understand that this happens to families in our country and all throughout the world," she said.