The chances are, however, that she will also be an illegal alien. The nation's capital is jammed full of Zoe Bairds and examples of the Peruvian couple she employed. More double-income parents live here than in any other American city and the pool of undocumented labour, mostly Hispanic, is deep. Given the chance to hire Isabella, the temptation to turn a blind eye to the layers of federal and state regulations concerning domestic employment can be overwhelming.
Often the applicant will ask for payment under the table to minimise the risk of being detected by the immigration authorities. Such an arrangement can cut the cost of 8-hour-a-day childcare by dollars 100 ( pounds 65) a week.
Couples who have been knowingly transgressing the law may be examining their consciences this weekend. Many others, though, as they contemplate the publicity surrounding the Baird nanny flap, may be discovering for the first time that they have been breaking the law.
A primary legal requirement is that wages paid to a domestic exceeding dollars 50 a quarter must be reported, quarterly, to the Internal Revenue Service (the tax office). According to the IRS, that is fulfilled for about only one quarter of the 2 million home employees in the country. It is permissible to take on an immigrant who does not have the proper papers, on condition that you can find no legal immigrant or US citizen to do the same job and that you apply to the immigration service for the person to be given legitimate residence status. That can take three years, during which time the person in question cannot start the work.
What makes going by the book costly are all the supplements to be paid on top of the wage itself, notably federal Social Security tax, which runs at 15.3 per cent. There is unemployment and accident liability insurance. The most benign employers will also pay for the most basic health care insurance. A typical outlay in Washington for full-time childcare would be pushed up from about dollars 250 a week to dollars 350. Many recoil from all the official paperwork too.
One young Washingtonian father admits he breaks the law and had previously thought little about it. 'We need the help and she needs the work,' he says. 'And I'm not running for Attorney-General.' He admits, though, that he would not take her on as a live-in help because as an alien she has no medical cover and, though healthy now, is 75 years old.
The risk that those illegally in the country might be exploited is obviously considerable. Tales are told of foreign couples, with no English, who work for virtual slave wages because they have been promised help in attaining legal status, only to find nothing is done for them at all.
Some happier cases have been reported however. For instance, one Washington couple paid for their new Peruvian nanny to fly back to Peru to straighten out her immigration papers at the US embassy there before she returned to continue in her position.