Talk

I would just give her the one month, maybe 6 weeks at a push. We had a similar situation. It was tough but we had the same concerns as your DH.

I would just give one month or maybe 6 weeks.
She never needs to know that your notice period was 3 months.

Tricky as you presumably still need childcare for the next three months. So I would just give the notice as required in your contract. Perhaps drop some hints that you are not that happy at work so it does not come as a complete surprise.

Are you going to look for a new job? If so then you may get that before your current one officially ends and so move straight in to that job.

I've always said 4 weeks isn't a lot so more would be nice

Yes she may leave you before / she may not

I've had jobs wait for me and they've got a temp and reason I got the job was the fact I said I wouldn't leave my family early - ie in the lurch

I would tell her now. I find a lot of nanny jobs start in September (I've been looking for September for months and most people had already set it all up.) so hopefully she can still see her 3 months out. It's really hard to find a job in a short space of time, many families will have already got a nanny in place for a months time.

Unless you are planning on giving her more than statutory redundancy plus all her accrued leave obviously I would give her at least 6-8 weeks notice, more if she has holiday booked during the next 3 months as she won't be around to look for work.

It's really stressful to be made redundant and to not know if you can cover your bills. A months notice is short.

Yes, you are slightly up the creek if a new job falls into her lap sooner rather than later but its the decent thing to do.

Wholeheartedly agree with Treadsoftly. It's just about being a good person. You are in a person to make someone's life a bit less scary and upsetting. Someone who looks after your children, and has a relatively precarious and low paid job. It's the right thing to do.