Nannies are pretty common here where I live. Our kids (3 1/2 and 1) have had one pretty much since they were born. It costs about $1000 a week to watch the kids during the day while my wife and I are at work.
After 3 years, our first nanny had to leave us for her professional career. But we still keep in touch with her. In fact, she came by to visit last weekend. They aren’t quite “family”, but they are a lot closer than just some “help” who shows up each day.
We never had a nanny, but my daughter did have someone that helped us everyday when she was little, and then first in school. Now we don’t even live in the same city, but that special relationship has continued. It’s wonderful.
Our friends have a nanny. They youngest are about 8 now and they’ve cut back her hours. She’s the only one home for hours at a time now that all the kids go to school.
She has taken up cleaning work in the neighbourhood to fill those hours, so she’s transitioning away from the job. They’ve employed her for something like 12 years now, so she’s basically a part of the family. She had her own daughter, so they hired a replacement nanny for six months or so when gave birth. She had a nanny of her own for a few years, which was interesting.
I expect she’ll transition to a new family in a few years.