"A relative to-"

I want to write: "The magazine is edited by Dr. SO-AND-SO, the Prime Minister's brother-in-law", but in the specific context that comes off too blunt. I want the pedigree-comment to be more in passing, like it's just another point on the list and not the main reason to appreciate this editor.
The following comes to mind:
"The magazine is edited by Dr. SO-AND-SO, a brother-in-law to the Prime Minister".
To me that sounds better, but still I'm skeptical about the grammar. Is this a legitimate expression?
Thank you!