English "nanny" for July 2014

I am looking for a native English speaking "nanny" to spend the mornings of July with my 3 kids (aged 6 and 4 - twins). Class location: Puerta de Hierro (Moncloa-Ciudad Universitaria not Majadahonda). Tasks would include help the kids get dressed and take them to the garden/ swimming pool until lunch time and play with them. Rates will be agreed based on applicant's cv and availability.