I understand your daughter´s fear. I´ve been there too.
I´ve pushed a stones measuring almost two inches.
I just could not believe it. A friend of mine pushed a couple larger than a quarter and quite thick.
It is amazing how elastic the bile duct can be.
What you daughter could do is to use a stone breaker for some time before she flushes. Gold Coin Grass from Sensible Health is wonderful and also Chanca Piedra tincture. Both shoul be taken on empty stomach. Both will help to crunch and softher her stones. then she shoul go for a flush.
The first flush is not always successful, as the liver may be well congested, but mine first flush was amazing and I pushed over 500 stones, the second was even better. I was fealful that a stone could get stuck as well, but Mrs Chang(from Sensible Health - you can always give her a call, she´s a sweetheart) had spoken to me and told that it is rare to have a stone stuck, but if it happened I should take Epsom Salt
to dilate the bile ducts and then repeat the ingestion of Oil plus juice.
Tell your daughter not to be afarid. flush do work is risk is close to zero.
If you need more details from a veteran please write. i´ve done 20 flushes so far.