Quitting advice

I have been a nanny for a family for a year and half. I’m currently on maternity leave tell the being of the year. Before I had my daughter I thought that I would be able to go back to work and care for my baby and the two year old twins that I have been watching. Now that my daughter is here I have no desire to go back to being a nanny. I am trying to think of a nice way to say that I won’t be coming back to work for her. I thought about letting her know that I’d come back for a little bit or part time tell she could find someone long term that she likes. Basically I would like to hear what you’d say or how’d you put it if you were in my position.