Thanks all.

As predicted I got a standard reply from Ofsted referring me to the EYFS. I do find it surprising that providers are left to interpret the rules themselves, no guidance offered, but they'll come down on you like a tonne of bricks if you get it wrong but I guess that's the way it is! I contacted my LA advisor again and they felt I should do a risk assessment and discuss it with the inspector on my registration inspection but I feel it would be too late for my friend to find alternative care if I had to say no at the last minute and I also feel they'll just refer me to the EYFS again. I'm not interested in nannying at her house and unsettling my own children and taking the out of our home for 2 or 3 days each week. So, I'm just about to let her know I can't have them both once I'm registered and am crossing my fingers that she'll keep sending the baby to me and can find a local alternative for her oldest boy but it's pretty booked up around here