George W Bush, his father said, had "some problems" but he had no reason to believe he used drugs - and never asked him. Mr Bush Jnr, favourite for the Republican presidential nomination, ran into a rough patch with the media over drug rumours. He gave reporters to understand he had not taken drugs for 25 years but refused to go back further.
In an interview for Fox News channel to be broadcast tonight, George Snr said: "We knew he had some problems but that he faced up to ... no different than most kids." He also endorsed his son's refusal to say more: "I do feel strongly about gotcha politics, about intrusiveness and I'm very proud that he's with that position."
As President, Mr Bush confronted rumours that he had been unfaithful to his wife, which George Jnr categorically denied on his behalf.