News on Jessie! Best news, her heart is fine. She has a congenital murmur, but bit isn't causing any stress or problems with the rest of the heart. Basically hers just works a little different.
On the kidneys, the official word is renal dysplasia. Basically her kidneys just aren't formed right and aren't working properly. You need at least 33% of kidney capacity to work normally, and she's at about 20-25%. It's something congenital, not a disease or infection. It's not treatable, but it is manageable with special food and some meds.
The thing we still need to figure out is if and how fast it's progressing. If it's not progressing, she'll live a normal lifespan with the treatment we're starting. If it's progressing, that means her kidneys will function less and less well until it's not enough. So that would be a decreased lifespan, but we don't know how much until we know how fast it's progressing. We'll have to test her levels a few more times a few weeks apart to know that.
So overall not fantastic news but much better than I was afraid of and definitely manageable to some degree at least. Thank you everyone for all the POTP! I know it's helped. If anyone has any advice on kidney diets, especially as far as what treats are good, we'd appreciate it.