After-school Nanny Needed For 2 Children In Watertown Mon-Wed

We're a family of four living in Watertown, with kids going to school in Newton. My husband Dirk and I are both Belgian (though met in Cambridge) and have been living here for nearly 20 years now. We have 2 kids, A (9, 3rd grade), and M (6, 1st grade) - they go to school in Newton. They are both quite athletic (and so have several sports activities) and also both take piano lessons. They also enjoy arts and crafts. We're hoping to find someone to pick up our kids from school from Mon-Wed (2. 40 p.m. on Monday, Tue and Wed can be as late at 3. 50pm) and drive them to their various activities/make sure they finish their homework and practice piano), and perhaps make them an easy/quick dinner too. Having your own car and having a clean driving record are a prerequisite. We just lost our child care so we're looking for someone to start ASAP.