Jackson's family say the firm, which organised his 50 farewell gigs in London, ignored fears over his health.Talking about her recent troubles, Jason Pfeiffer said of Paris: 'It is tough for Paris to be without the main influence in her life at this very challenging time.

According to evolutionary theory, intra-sexual competition will concern mainly those traits that are attractive to the opposite sex.

The American evolutionary psychologist David Buss found in the eighties that intra-sexual competition takes two primary forms: self-promotion and competitor derogation.

' He was half joking so I joked, “Oh, I just look at her and she gets pregnant'.

The Jackson children are due to be witnesses in a £26million lawsuit against concert promoter AEG Live.

Filed against AEG, the company behind Jackson’s ill-fated ‘This Is It’ tour, the suit includes all three of the icon’s children as well as his mother Katherine and alleges the company contributed to Jackson’s death by pushing him to work too hard ahead of the tour and by hiring the doctor responsible for giving Jackson the drugs that killed him.‘There was a whole lot that Michael Jackson or his family wasn’t and isn’t being forthcoming about,’ said the Post’s source at AEG .

‘The drug use by Jackson, his use of alcohol, his relationship with his own family, and the identities of the children’s parents.’A former Jackson bodyguard named Matt Fiddes asked for a DNA test to prove that he’s father to sapphire-eyed Paris shortly after Jackson’s death and former child star Mark Lester has said he, too, may be Paris’s father.Influenced by Darwin (and by the fact that until recently most researchers were men), most of the research into intra-sexual competition has focused on the struggle between men to gain sexual access to women.Only in the 80s did science begin to investigate in earnest the same phenomenon on the other side of the gender divide: female competition for a suitable male.A host of studies in recent years have shown convincingly that the traditional view of women as passive and uncompetitive is wrong.Women, it turns out, are engaged in a competition of their own, aggressively jockeying for position in a battle to secure a suitable mate.On closer inspection it also becomes clear that male competitiveness, aggression and violence are often directed primarily at other males: on the battlefield, on the playing field, in the office, at the bar, or on the street.