Thanks everyone, v helpful.

Nannies dont have a ratio for children, but for families instead. A nannyshare cannot be with 3 families otherwise they will need to register as a childminder.
In your situation it is up to the nanny and the families how many children they feel comfortable with.

My children's nanny cares for my four children. She also has a lot of experience looking after two or more children. Plus, she worked for me a year with the three children before I had my fourth so she could already handle my clan. I think in your case as it would only be all of them together after school, then it would not be as demanding. Ultimately it depends on how comfortable the nanny and family(ies) is/are with the arrangement. (I am not aware of a specific ratio for nannies as they do not have to be registered).

Hello,

I'm looking into a nanny share one day a week, but I suspect it may not work after 3.15pm - when the 2 x 5 year olds need picking up.

Am I right in assuming the ratio for nanny's is the same as for childminders?

Thanks!