Babysitter Needed For 2 Children

We are looking for a great babysitter for mainly 2 children one with medical needs (medicine administration)(ages7) also 13-year-old for afternoon and weekend care. We have a full-time nanny who works with us in the mornings, and this is to supplement when she cannot work. We would prefer someone who could help out with light housekeeping, who has their own car, who does not smoke and who is CPR certified. Starting ASAP will be looking for extra help care to help manage afterschool activities and weekend activities for this busy family. We are looking for someone who is local year-round not just during the school year or on summer vacations and is comfortable doing a night or two overnight if need be a few times a year. thank you.