Well, I guess Fading Kitten Syndrome isn't genetic or the twin would have had it too.
If he was as big as the others, and suddenly stopped to grow, and even rapidly fell down in weights, I suspect some body system stopped to function... So it was his fate to be no more.Good question. He wasn't until last week. He actually has a twin that was identical - couldn't tell them apart. He just stopped eating. I put him back on the bottle and he would get better but only for short periods of time. Who knows?