Very possible some might. When you interview a friend circle or distant family members you get a lot of hearsay, but information that might peak your interest.
Say they interviewed a few friends and they reluctantly disclosed that AG hated her mothers guts or has been arguing lately, and her husband is very controlling and she'd do anything he said. Well, there's no smoking gun there but it would certainly give you an inclination on how to proceed.
But people are reluctant to disclose such things, and sometimes they divulge when pushed but qualify it with "but I don't think she'd ever hurt her...." etc. Some people are more guarded and don't have a huge friend/family circle -- it is something we haven't really heard much of and as an investigator I'd really want to know.
I would imagine they did personal interviews, maybe even some financial forensics, phone records of the family members, but again you have to tread lightly in this victim/potential suspect balance.