FeLV Advice

Hi r/CatAdvice, I am wondering if anyone has advice on coping with and managing FeLV and/or words of wisdom. One of our two cats (littermates, both 3.5 years old) just got a positive ELISA test for FeLV after noticing slightly abnormal bloodwork (the other cat had normal bloodwork so we didn’t run a follow up test right away). Both kitties had negative FELV tests as kittens, so we didn’t think this was a possibility as they are indoor only and have never interacted with other cats outside of the short time in a foster home with their mom and other littermates. We are running a PCR test on the positive cat and testing the other cat this week. Any advice to calm my nerves? Google is quite the depressing rabbit hole for FeLV.