blocked vent

Have just noticed that my welsummer has a blocked vent!!!! have managed to clear it by soaking and gentle manipulation!!!! She is a bit sore round her back end any advice what to put on it or should i just bathe it in salt water. Is it caused by not drinking enough or is it just one of those things that some chickens are prone to.
We have isolated her so we would  know if she has passed anything, and she has passed 2 massive poo's. Can this be fatal if left to long!!!!!
Cheers
Chicken Little

don't think she is egg bound, although as i have 2 welsummers only one is laying  how would i know? I suppose now she has cleared her blockage she will be able to lay.
She was very subdued before but is now eating/drinking since she has done a poo!!!!!

Hi there,

I've never tried it, but have been recently told that a bit of flax seed oil in her diet will help her pass any stuck eggs.  Not sure if this is folklore or not though. Has anyone tried it?

Vi