Absolutely give notice, but with that kind of history I'd also include the reasons for giving notice. Things may not change for you buy they have a chance of improving for both the family and the next Nanny they hire.
When it comes to discipline, we need to know your rules well enough that you can back our calls. The first things kids want to know is if they can play us against their parents and vise versa. That makes maintaining structure difficult for everyone. Working together is everything.
The first week is all about getting to know the kids and their family. I do that in everything from games to chores to meal-time. Where possible, it's all about asking lots of questions.
I tell parents to always confirm with a doctor (to rule out anything serious) in a non-emergency appointment. When growing pains are confirmed, I suggest something to distract the child until they pass. I suffered them myself so I'm very sympathetic.
I always ask families to describe their family vibe, parenting style, and values.
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