The daughter of the editor of the Guardian, BellaM — Isabella Mackie — has been identified as the poster of a controversial comment on a website she was moderating.

According to the website, CiF Watch — set up specifically to monitor incidents of anti-Israel bias on the Guardian's Comment is Free site — BellaM intervened in a series of posts that followed an article by the Muslim writer Ed Husain, attacking the columnist Melanie Phillips.

BellaM is employed as a staff moderator on Comment is Free. Her job includes deleting comments which are offensive or libellous. But in the course of moderating the comments on the Husain article, she decided to make her own contribution.

She wrote of Ms Phillips: "I imagine she's like that character in Little Britain who is violently sick every time she hears the words 'black' or 'gay.' Except for Melanie, the word would be 'Muslim.'

In the wake of BellaM's post, there was, it is understood, an embarrassing internal row in the Guardian. Though she was not disciplined, she was, as the JC reports today, "reminded of the paper's guidelines that staff posting on the site should uphold a high standard of civility and avoid any behaviour that brings the Guardian's good name into disrepute."

BellaM, according to CiF Watch, is actually Isabella Mackie. Mackie is the maiden name of editor Alan Rusbridger's wife.

A Private Eye report noted that "Isabella Mackie, a recent graduate, had the grace to use her mother’s surname when taking a job on the Guardian’s website to disguise the act that she is the daughter of the paper’s editor, Alan Rusbridger."