A lot of times in this biz, there's not equanimity between working brothers. Neil and Danny Simon is arguably another case of this, but it's a little more equitable than, say, Mark and Lawrence Kasdan or William Goldman and his brother. I know, I gotta stop harping on those examples. But Neil and Danny went a little bit farther than the average one-sided flameout story. Danny got stuck in the TV ghetto for good, but Neil stepped on his neck and clawed his way out with Danny's help. Apparently, it was Danny who came up with the idea for The Odd Couple! But Danny was unable to bring it to fruition like Neil, and so full credit to Neil it was. The film bug bit Neil pretty hard and he wasn't able to give it up, no matter how many movies about suites got to be too old. I have yet to see one of them, but I hear they're quite witty and urbane. You know, the kinds of movies they used to make in the good old Hays Code days.
And then, in the go-go 80s, time to cash in on the more personal stuff, and another trilogy was borne: Brighton Beach Memoirs, Biloxi Blues and... something else. Frankly, everything after that's kind of a blur for Neil, especially Odd Couple II and the Heartbreak Kid remake, I'm assuming.