The most ominous sign yet for the future of the Murdoch empire is the claim, made in the forthcoming issue of the magazine Vanity Fair, that for nearly a year Rupert's children have been "in family counselling with a psychologist over the issue of succession". Buccaneers don't go to counselling. In Shakespeare's plays, sibling rivals for power don't seek psychological help; they kill each other. That is how they prove their ruthlessness. Rupert Murdoch would never have become the world's most powerful media tycoon if he had discussed every decision he made with a shrink. Yet Lachlan, Prudence, James and Elisabeth are reported to have turned to a psychologist to advise them what to do when the old man finally decides to pack it in.

Rupert Murdoch, like a mafia godfather, has always made clear that he wants one of his children to succeed him as chief executive of News Corporation, and his clear favourite before the phone-hacking scandal broke was James, whom he had already promoted to be head of NewsCorp's British subsidiary, News International. But since then, according to Vanity Fair, their relations have become strained, and Elisabeth has been busy stirring it by demanding the heads not only (successfully) of top executives Rebekah Brooks and Les Hinton but also (unsuccessfully) of her brother James, who faces further interrogation by MPs next week amid new evidence that he may have known more about the News of the World's phone-hacking practices than he has so far admitted.

This sounds ruthless of Elisabeth, but perhaps not ruthless enough, because she seems to care rather too much about family harmony. According to the magazine, the counselling started at the beginning of the year when Rupert was considering giving up his CEO title and wanted James to be groomed for the job. "Lachlan, Prudence and Elisabeth had discussed the move extensively with James," it said. "They told James that if they worked together as siblings they could help him and their father have a better relationship, and that together the kids could hold Rupert to account to be a mentor to James and not undermine him."

This is all a bit muddling. I haven't seen the full article, but I'm not clear from the summaries how Elisabeth's compassionate attitude towards James is compatible with her reported demand of her father that he ask him to relinquish, at least temporarily, his job at News International "for allowing the phone-hacking crisis to spiral out of control". But the general picture is clear enough. It is one of a doddering old man ready to give up power, but unable to do so because of divisions and animosities within the family.

The article talks not only of tension between him and James, but also of distrust between him and Elisabeth's husband, the public relations man Matthew Freud. It says James's siblings agree he is "the best-suited to be the heir apparent", but somewhat half-heartedly so, because they find him too "aggressive and alienating in his public postures". At the same time, James's position seems to be increasingly precarious, and his chances of succeeding his father ever smaller. These are not problems with which a psychologist would be much help.

I have real willpower, Mr Obama

Barack Obama's latest medical check-up, which found him "in excellent health and 'fit for duty'", also contained the exciting news that he is now "tobacco free". This can only mean one thing: that after years of obfuscation on the issue, the US president really has given up smoking. But we still do not know when or how.

The relationship between Obama and cigarettes is one of the great mysteries of our time. His wife Michelle reportedly made it a condition of her support for his presidential ambitions that he give up his 20-year habit. Even so, after he had won the election, he admitted he hadn't given up completely: "There are times where I have fallen off the wagon."

But it seemed pretty clear to me that he would have to stop completely when he came to live in the White House, not only because he would be under Michelle's watchful eyes, but also because his secretary of state Hillary Clinton, in her former capacity as first lady, had declared the White House a smoke-free zone. But did he actually do so? There is no way of knowing, for not once did he say whether he had or hadn't quit.

Since you would have expected him to boast about it if he had, I began to doubt whether he had the willpower I showed when I gave up out of solidarity with him on his inauguration day, 20 January 2009. Was I made of better presidential material than the president? Perhaps in fact he gave up long ago, but it would have been very odd of him not to tell anyone.

Who needs two mobiles?

The other day on a train I sat next to a teenage girl who was fiddling with two mobile phones. It seemed strange that she should have two phones, for she only had one short conversation on one of them during the 40-minute journey. I can't think why anybody should want two phones, except perhaps, an international drug dealer. Yet I read that the number of active mobile phones in Britain is now 76.4m – considerably more than one for every man, woman and child in the country. Perhaps someone can tell me why.