Brown sugar in warm water...
You can buy a fruit derived laxative that I had to take after my gall bladder op... Works in minutes! You just get it over the counter. I'm guessing that you could use it for kids.
Coloxal kids drops?
I had this same issue after my op,all the pain killers made me bind up and I couldn't keep any foods down as I was so clogged up. They gave me an enima at the hossy and it all ( and I mean all) came out in minutes... It didn't hurt either as the liquid they put in my bum made it all lubricated... Don't know if that would be an option??
Also milk is a natural laxative too...
Hope she gets some relief soon xo