Perkins is back in Winchester, disappointed, the chain of events still turning in her mind.
"I went all the way out there basically with the hope to see something in his eyes, some type of remorse, anything," she said. "But I saw nothing, absolutely nothing. I was completely shocked by his change of plea, so was the judge."
Sites entered his guilty plea on June 28.
In her speech to the judge, Perkins described how William Sites used a hammer to bludgeon her mother, Jan Sites, in the head then let her bleed to death. She was told by authorities that he put her mom's corpse in a recliner for three days, used her debit card to buy a hacksaw from Home Depot then dismembered her in the bathtub. He put her body parts in trash bags then tossed them in bins throughout their apartment complex while walking their dog.
For Perkins, who was adopted as a baby and had just reunited with her biological mother in November 2004, the sentencing was meant to be a relief. She had been exchanging letters and phone calls with her mom, and when the responses stopped in September 2005, she became concerned.
She filed the missing person report with Las Vegas authorities that led them to question William Sites.
"This was like a huge closure moment, and there was no closure," she said Monday about last week's hearing. "I think (William Sites) is grasping at straws, he's trying at the last minute to fight for his life."
Perkins won't be at his sentencing should it occur today, but said she got what she needed from her trip to Las Vegas last week.
"The main thing I wanted was, Is he gonna go up there and say â??Hey, I'm sorry?'" she said. "By the look in his eyes, he's not sorry anyway. I went there and I didn't see it. I saw nothing at all. It's sad that this is the way my journey has ended in finding my birth mom."