As detectives piece together what happened, we're hearing from her family about their sudden loss.
Police expect to be at the scene for another day or two, trying to solve this crime.
Allison Feldman is from Minnesota, attended the University of Arizona and moved to the home in Scottsdale about eight months ago.
Now her older sister, Kelly Weinblatt, says the family can't make sense of who would do this.
Police methodically gathered evidence from the home near Osborne and Pima where Feldman was found dead around 4 p.m. on Wednesday.
"Everything was going perfect in her life right now. She and Alex had been dating 10 months.. they were talking about getting married.. all of a sudden she was talking about having kids," said Weinblatt. "There was nothing wrong in her life right now, everything was positive."
Weinblatt says her sister texted their mother around 8 p.m. Tuesday night. That's the last anyone heard from her. She says her sister's phone went right to voicemail Wednesday.
"No one could get a hold of her all day Wednesday.. she didn't have her phone on, which is not like her at all. She's in medical sales, so her phone is her life," explained Weinblatt.
She also says Allison's boyfriend, who lives in Phoenix, was also concerned.
"I think he reached out to my parents to say, hey I haven't heard from Allison, is she traveling? Because she travels for her job. Then my parents said, no we can't get a hold of her either. Then everyone kind of started panicking," said Weinblatt. "My dad called Scottsdale police to do a drive-by, probably around 5 Phoenix time. In the meantime, her boyfriend gone over around 4 and found her and called 911. Her boyfriend was there pretty regularly, he was so upset he wasn't there... he's blaming himself.. the whole thing is horrible."
Weinblatt says her sister recently got promoted at work and had a wedding she was going to attend this weekend.
Police have not named a suspect and are not released how she was killed.
There was a burglary call nearby around the time Feldman was found dead, but police do not believe that's connected.
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