The wife of Democratic presidential candidate John Kerry has been forced to apologise after criticising First Lady Laura Bush in a newspaper interview.
Mrs Heinz Kerry 'forgot' that Mrs Bush was once a teacher
Heiress Teresa Heinz Kerry, 66, told the USA Today newspaper: "I don't know that she's ever had a real job."
Mrs Bush has previously worked as both a teacher and a librarian.
The aspiring First Lady, who inherited the $500m Heinz fortune, later said she had "forgotten" about Mrs Bush's "important" careers.
In her interview, Mrs Heinz Kerry said: "I don't know Laura Bush. But she seems to be calm, and she has a sparkle in her eye, which is good.
"But I don't know that she's ever had a real job, I mean, since she's been grown up."
But Mrs Bush, 57, is well known among voters for her previous jobs, and is often referred to as "The Librarian".
Mrs Heinz Kerry quickly apologised for her remarks.
"I had forgotten that Mrs Bush had worked as a school teacher and librarian, and there couldn't be a more important job than teaching our children," she said in a statement.
"As someone who has been both a full-time mom and full-time in workforce, I know we all have valuable experiences that shape who we are.
"I appreciate and honour Mrs Bush's service to the country as First Lady, and am sincerely sorry I had not remembered her important work in the past."
President Bush's advisors were quick to capitalise on Mrs Heinz Kerry's mistake.
Senior advisor Karen Hughes told CNN that Mrs Heinz Kerry had blundered even in her apology.
"She seems to have forgotten that being a mother is a real job," Ms Hughes said.
"I think her comment threw an inappropriate wedge between women who choose to work at home and women who choose to work outside the home," she added.