yes it will be difficult to get a visa,
from http://www.ukvisas.gov.uk/servlet/Fr...=1018721068341
How do I qualify as a domestic worker in a private household?
You must be able to show evidence for the following.
You are aged over 18.
You have been working as a domestic worker in the same house as your employer for at least one year immediately before your application, or you have been working in a household that your employer uses regularly for themselves for at least one year immediately before your application, and you can show that there is a connection between you and your employer.
You intend to travel to the UK with your employer, your employer’s husband, wife, civil partner, eligible partner or your employer’s child who is under 18.
You intend to work full-time as a domestic worker in the same house as your employer, or in a household that the employer uses regularly for himself or herself, and you can show that there is a connection between you and your employer.
You do not intend to work in the UK except as a domestic worker.
You can support yourself (as confirmed by your employer) without needing help from public funds.
You are a domestic worker if you are providing a personal service linked to the running of your employer's household. Examples include chauffeurs, gardeners, cooks and nannies.
the Nanny/Domestic helper Visa is mainly intended for the British diplomat who worked abroad and finishing their duties, they want to take their nanny/helper with them in the UK.
