I think she is very lucky!
I've been a sole-charge nanny for 24 years, have excellent references and have looked after children from newborn to 14 years, some with special needs.
I charge £200 for 24 hours proxy parenting!
Maybe I should up it.
I don't really consider weekend proxy parenting as work, I don't do any of my nursery duties, I just have fun with the children! I obviously care for them well and feed them, but we eat out, go to fun places, etc.
I am working this weekend, parents go away friday at 1pm, will be back on monday morning but going straight into work. I will get £220 per 24 hours and £15 per hour any extra hours, (I am working abroad for very generous employers!) and I know I will get a small gift from where they visit!
But I would not expect this, this is what they told me they would pay me, but if they came back and said next time it will be £200 per 24 hours, it would be fine as that is in my contract.