Taking time off...

There is no magic number. It will depend a lot on your state practice requirements and your current skill set. I would highly recommend that you try to get a part-time gig that will help you keep your skills sharp. You also will feel more confident when, or if, you venture back into the full-time world. I stayed home for 3 years while we lived overseas, I had no problem getting a job when we came back stateside. That was a while ago though and the job market has become more specialized and competative. I did volunteer at our local hosptial which gave me something to put on my resume to fill in the blank for those three years.

I would recommend taking a prn job with minimal work requirements to keep up your skills while still leaving time for your family responsibilities. I am glad I did this. Having complete control over my work schedule, earning money(nice per diem rates), and having something outside of home and childcare that was mine was sanity -saving. That small stream of income made a bigger difference than I had anticipated too.

Keep your hand in if you can, even a couple of shifts a month will do that.

This is so smart and in nursing we are lucky that options like this exist. You're right you can't predict the future. What if your spouse lost his job you'd already have your foot in the door.