Prolapse and nasty white dripping poop on backside
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Wash her up again and give her a good soak in epsom salt bath. Give her some extra calcium (liquid calcium or crushed Tums). Once she is cleaned apply some hemorrhoid cream or honey and gently push the prolapse back in, if it doesn't stay you may have to repeat or hold it for a few minutes. Apply some more hemorrhoid cream or honey and put her in a dark quiet area with food and water to see how she does.
The white discharge could be Vent Gleet which is a fungal/yeast infection. You may have to treat her with Nystatin. Some people apply an
athlete's foot anti fungal cream to the vent to help with the discharge, but since she is having prolapse problems as well, you may want to just use the hemorrhoid cream for at least the first day or so to help reduce any swelling.
Here's more info on both: