Their aunt Marilyn Galindo believes the brother and sister protected one another until the very end.
"They had each other's backs through, through everything," she says. "We will never know actually what happened, but we would like to believe that they had each other's back when everything happened."
On Monday morning, Hanford Police arrived at the family's home on Orange Street to find Ryan and Zach stabbed to death. Ryan's ex-boyfriend, 20-year-old Garrett Leyva, is accused of killing the siblings. He was also inside the home and had stab wounds.
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During their two-year relationship, Leyva was no stranger to Ryan's family.
"Every interaction we have had with him, myself personally, he was always very respectful," says Galindo. "He would come up to us and give us a hug and tell us hello."
Galindo says Leyva was quiet, a member of the Army reserves, and never gave the family a reason to worry about their relationship.
"I know that if my sister even had some kind of hint or intuition, she would have said something to all of us to help Ryan get out of the situation she was in," she said.
Authorities say the couple broke up over the weekend.
"It was nothing out of the ordinary that would even remotely raise some red flags to us," said Galindo. "She was done and this young man could not accept it."
The family hopes the autopsy and investigation will reveal answers about what happened inside the home Monday morning.
"It's not the way of life for a parent to bury their child let alone having to do two at the same time."
Leyva was hospitalized for his stab wounds and is expected to survive. He hasn't been booked into King's County jail yet.
There have been two GoFundMe's established for the victims' parents.
Click here or here if you want to contribute to one of them.
If you are the victim of domestic abuse, or you know someone who is, there is help available 24/7. In Fresno County, call the Marjaree Mason Center at (559) 233-4357. In all other locations, call the National Domestic Violence Hotline at (800) 799-7233.