She has blood coming out of her vent

Hello folks,
One of my girls has got blood around her vent. She has layed an egg today, but it had a very soft shell (almost like rubber). She has also done a poo that was about 70% blood.
Any ideas what could be wrong?

Thanks in advance

Andrew

she seems fine,,,,,,,,,,,,,,,,a red bum,,,,the others are pecking a bit,,,,,,,,,,,,,,

no,,,,nothing seems to be sticking out