We're looking for an au pair for the first time. We're likely to need about 27-30 hours a week for before & after school childcare, till around 7pm. I've heard people say that 2 evenings babysitting are generally included / expected. How does this work? Are 'babysits' only when the children are in bed i.e. if we stayed out for the evening, we'd have to pay overtime from her usual end time of 7pm to the kids' bedtime at 8pm?