Well, that would be nice, wouldn't it?
But not possible in our case for anything other than short term.
In the short term, we could pay the mortgage, council tax, utilities, broadband & mobiles, essential insurances etc., and groceries and petrol, and put by money to tax the car, etc.
But we'd have to cut things like pet insurance, holidays, entertainment, buy no clothes or 'stuff' for the house, be very frugal with birthdays and basically stop paying for non-essentials. Which is unsustainable in the medium-long term.
However I guess there would be a redundancy payment, we have savings in case of "oh fuck" moments, and we would be looking for jobs - even NMW jobs - to supplement all that. So I wouldn't touch the "oh fuck" money unless it was desperate, and that means chopping all the other expenses first.
I'd certainly consider childcare - your nursery bill - to be a luxury if one parent was at home and available to do childcare. So your relative is bonkers on that point alone, as even though we have savings I wouldn't spend them on that over Dad being home to look after them.