I caught these 3 guys lounging on my bed together the other day and wanted to share. They are all sons of a feral cat that I spent years trying to trap. When I lived on my "farm", the feral cats liked to have their kittens elsewhere, then bring them up to my house because somehow they all knew that I fed them there. More often than not, they would bring the kittens up, drop them off and disappear before I could trap them (of course this all changed once I bought my own trap and didn't have to borrow one when a new cat showed up).
I spent 5 years trying to trap these cat's mother (if I only knew then what I know now). She was a short haired red tabby with distinct enough markings that I knew it was the same cat. The first kitten she left for us was Bob Marley (on the left) who is now 11 years old. The second set of kittens she left were Pinky (middle) and Ruby (OTB), now 8 years old. The last set of kittens she left included Lucky Pierre (right) now 6. Since I finally had my own trap, I trapped the entire family and all but Lucky had FeLV. Somehow Lucky fought it off by himself. The mom looked most like Lucky.
It is very weird, but even though there is 5 years between these cats, it's almost as if they recognize that they are blood related. They hang out with each other more so than any of the other cats in the house, and I've never witnessed any type of issues between them, even when Lucky was first introduced to the house and while some of the other cats hissed, Bob and Pinky came up and groomed him.