Part Time Nanny Needed For 2 Children On Upper East Side

We are looking for a part time nanny for two young children (2-year-old boy and 3-month-old girl). We are ideally looking for someone who can help at least two days a week (Monday and Wednesday from 10:30-5:30). There may be the possibility of some additional days/times week to week. The primary task would be helping with the 2-year-old, picking him up from nursery school, taking him to playdates, feeding him lunch, helping get him down for a nap. In addition, it would be great if you could help as needed with the 3-month-old - changing diapers, feeding occasional bottles, burping/soothing - especially as we attempt to establish a more regular feeding/nap schedule over the next couple months. We also have a 12-year-old girl, but she's largely self-sufficient and wouldn't require any care, but can be helpful.