The family of 24-year-old Yasmine Uyar of Rahway first disclosed the news late Saturday.
Young Sebastian Rios had been found unharmed at a family member's home in Monterey, Tennessee, late Friday.
His father, Tyler Rios, 27, of Highland Park was also captured, acting Union County Prosecutor Lyndsay V. Ruotolo and Rahway Police Department Director Jonathan Parham said.
Uyar’s body was later found in a wooded area off Route 40, they said.
Rios will be extradited to New Jersey to face what currently are kidnapping charges in Superior Court in Elizabeth. Additional charges were expected in connection with Uyar’s death.
The news was crushing for loved ones, friends and others who held a vigil Saturday night in Highland Park.
Sebastian hadn't shown up for daycare Friday and Uyar didn't arrive for scheduled work shifts, they said.
Responding to loved ones' concerns for her welfare, Rahway police went to Uyar's home didn't find anyone there.
New Jersey State Police then issued an Amber Alert that was sent to private cell phones, broadcast on electronic billboards along highways in New Jersey and beyond and shared on social media.
Loved ones weren't sure exactly when the trio went missing because Yasemin Uyar had been packing for a move, her mother, Karen Uyar, told PIX11.
Rios could have taken them to any number of destinations, including Georgia, she said. He reportedly has connections in Newark, Paterson, Lawrenceville, GA, and Phoenix, AZ.
Rios assaulted her daughter several times despite a restraining order, Uyar told PIX11.
Rios was convicted in Middlesex County of aggravated assault on a domestic violence victim and was sentenced to 180 days in jail with three years of conditional probation in February 2020, court records show. Yasemin Uyar was the victim, a close family friend told Daily Voice.
Rios had agreed as part of a plea deal to complete anger management classes and not have any contact with Uyar again.
Records show that Rios had also been arrested at least twice in Arizona in 2019, once on assault and unlawful imprisonment charges and another time for allegedly firing a gun.
Karen Uyar said her daughter and Rios had known each other since she was in high school but hadn't been involved since after their boy was born. She said he could become violent, particularly when he drinks.
"While my family grieves the loss of Yasemin please remember she wasn’t just a DV (domestic violence) victim," the grieving woman posted late Saturday on Facebook. "Her life will be celebrated as her greatest gift to this world, Sebastian will still need all of our love and support."
Funeral arrangements were pending, she said.
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