Bristol Palin, the daughter of former Alaska governor Sarah Palin, has said sorry after her younger sister used a homophobic slur.

Willow Palin, 16, told a Facebook friend this week that he was a “faggot” and “so gay” after he criticised Mrs Palin’s reality TV show.

Bristol initially joined in the row, telling the user named Tre: “You’re running your mouth just to talk shit.”

But yesterday, she added: “Willow and I shouldn’t have reacted to negative comments about our family. We apologise.”

Willow, who has not commented, is understood to have deleted her Facebook account.

The family was defended by Republican gay group GOProud, which said Willow was being unfairly criticised.

The group told TMZ: “The slur used here is one you could hear on the streets of West Hollywood or Chelsea every day of the week. Apparently, it’s only a homophobic slur when it comes from the daughter of a conservative female leader.”

“Make no mistake; this is all about destroying Sarah Palin by any means necessary.”