This would be a Terrible deal for the blues. Fabbri is a young and upcoming talent that is gonna be cheaper and more valuable on the blues roster for the next 5-7 years. He has 1st line potential and has shown how good he can be at times (last year's playoffs). Little is too old, a ufa(will want a l9ng term deal into his 30s) and is too injury prone to rely on. He also isn't a good enough get to build around as your number one center.
This Little is injury prone thought is pretty unfounded.
Games played in his NHL career
79,79,76,74,48*,82,70, 57, 59
He missed a total of 20 games in his first 4 seasons.
Went back to back years with no games missed and then missed 12 3 years ago.
The injuries from the last 2 years could and do happen to anyone.
2015-16 was a bad luck stumble where he got hit while falling.
The knee on knee in 2016-17 would have injured anyone.
It's like people say someone is injury prone as if other players would not have sustained injuries from those situations.
That being said...
Don't make a trade like this within your division.