Forgot to mention The Keys to December," by Zelazny. I assume he probably wrote a lot of short sci-fi or fantasy, but other than this I've only read his novels.
Anyway, whimsical narration to start off with, but ultimately heartbreaking. Someone's review
here; and below are the first few paragraphs to give the flavor:
BORN OF MAN and woman, in accordance with Catform Y7
requirements, Coldworld Class (modified per Alyonal), 3.2-E,
G.M.I. option, Jarry Dark was not suited for existence anywhere
in the universe which had guaranteed him a niche. This was
either a blessing or a curse, depending on how you looked at it.
So look at it however you would, here is the story.
It is likely that his parents could have afforded the temperature
control unit, but not much more than that. (Jarry required
a temperature of at least -50 C. to be comfortable.) It is unlikely
that his parents could have provided for the air pressure control
and gas mixture equipment required to maintain his life. Nothing
could be done in the way of 3.2-E grav-simulation, so daily
medication and physiotherapy were required. It is unlikely that
his parents could have provided for this.
The much-maligned option took care of him, however. It
safe-guarded his health. It provided for his education. It assured
his economic welfare and physical well-being.
It might be argued that Jarry Dark would not have been a homeless
Coldworld Catform (modified per Alyonal) had it not been for
General Mining, Incorporated, which had held the option. But then
it must be borne in mind that no one could have foreseen the nova
which destroyed Alyonal.
Below is the cover of a 2009 release of his collected stories - apparently in two volumes; so likely this story could be found there. Worth the read, especially if you like his other work.