toddler and food

what is the longest your toddler has gone without eating any drop of food ?
my daughter has a kidney infection and RVS .
my daughter has not had any food what so ever in 10 days and has lost 4 pounds in two days and the doctors don't seem to concerned . they say if she isnt eating food still in a week to bring her back .
I just want reassurance that this is semi- normal and that she'll eat again .
TIA

when cam was super sick last year i think we reached 8 days of not eating anything but thankfully was still drinking here and there. on the 8th day i finally got him to start eating yogurt