Flexible Nanny Needed For Two Young Children

I'm a single father looking for a nanny willing to work 2-3 days a week in the afternoon for my two girls, aged 3 and 5. I will have them either M/T or W/Th, rotating which each week, and occasional Fridays. It's possible their mother who lives close by will want to use the same caregiver on her days as well. I am looking for a caring, fun, individual who can pick up my girls from school at 5 p.m. and stay with them from 5-6 p.m. at least, some days into the evening. My ideal candidate is someone who is flexible and able to occasionally stay with the girls through the evening as my job dictates.