Enlarged Liver - Possible FIP?

My 4 month old kitten has been dealing with a lot of ailments since I got him. He's had a cold, intestinal bacterial infection, low grade fever for weeks, and now a cough. I took him in for an X-ray today, and it's confirmed he has pneumonia and his fever has gone up, but they also found that he has an enlarged liver. From the symptoms, they're thinking FIP? What causes an enlarged liver, and is that a symptom? Also, he's eating and drinking just fine and acts for the most part fine until he starts coughing. Any other ideas? 

With that said, I have set up a Go Fund Me account for him in order to get the next step in care as they're wanting to hospitalize him for a few days so he can have a fighting chance. Check it out and please share, share, share! This little one needs it, and pet insurance won't cover his pre-existing and congenital conditions.
Best, 

- L

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