Bless you for saving Gordy and his litter mates.
I am sorry Gordy has this trouble.
Blood from the rectum is usually caused by worms.Most kittens are born with them
You can get an OTC wormer in Walmart any pet store or online at ebay or amazon.
Get Excel, Profender or Stronget
If you find Gordy does have loose stools add one tablespoon of rice cereal or boiled white rice to a jar of baby food chicken with no onion powder OR a can of cat food. Feed until his stool is normal for 24 hours.
Also give one half tsp a day of plain yogurt for good bacteria.
If he gets dehydrated give him tuna water drained from the can.
Please let me know how he is doing .
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