"Mother's Helper" Needed to Assist with Two Young Children, Light Housekeeping

We are looking for someone to help us with childcare (two girls, 2 yo and 3 mo) and light housekeeping. Both parents are self employed and work from home: mom works very part time (irregular hours) and dad works full time (roughly 6-2). Basically, we need someone to help Mom get done all she needs to get done, without neglecting the children, in order to protect Dad's work hours. We would prefer someone who is CPR certified and who has a car / willing to drive. You would occasionally be asked to take the children to play dates, watch them alone in our home, etc, but the vast majority of the time Mom would be with you and the kids.