Native speaker for class with 4-year-old in Puerta de Toledo

I'm looking for a native English speaker to take over a class with a 4-year-old boy in Puerta de Toledo. You would pick him up from school and go to the park or to his house and play in English. I'm looking for someone who has experience with children and is patient. The class specifics are the following:

Days: Tuesdays and Thursdays from 16:00-17:00 in Puerta de Toledo (both the school and house are there)
Pay: 15-18 euros/hour
Starting date: Starting the second half of September 2014 and continuing until June 2015 

I won't be able to consider non-natives under any circumstances. Don't hesitate to send me an email if you have any questions!