Baby Kennedy Hoyle's Big Sister Grieving the Deaths of Her Mom, Newborn: 'All She Does Is Cry,' Says Grandma

Police in Memphis are still searching for baby Kennedy, whose father, Brandon Isabelle, 25, admitted to throwing the newborn into a freezing cold river and fatally shooting her mother, say authorities

Danielle and Kennedy Hoyle. Photo: Facebook; TBI

On Monday, as she lay in a Tennessee hospital bed just after giving birth, Danielle Hoyle couldn't wait to hold her newborn, Kennedy Hoyle.

"I been waiting on them to bring her to me all morning," the 27-year-old new mom from Whitehaven wrote on Facebook.

Danielle had no idea she would only be able to hold her baby girl for the next day and a half.

On Tuesday night, the baby's father, Brandon Isabelle, 25, shot Danielle in the head in the Whitehaven section of Memphis and threw their baby daughter into a nearby river, according to an affidavit of complaint obtained by PEOPLE.

Brandon Isabelle. Memphis Police

"It's a lot," Danielle's distraught mother, April Campbell, told PEOPLE.

"Danielle was the kindest lady you could ever meet," she says. "She didn't bother anyone."

Danielle doted on her young daughter, Riyah, 10, who was excited to become a big sister, says Campbell.

Riyah and Danielle "were best friends," Campbell said.

"All my grandbaby knows is my daughter," she said of Riyah. "All she does is cry and say she wants her mama."

Holding back tears, she says, "This has taken a toll on the whole family."

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Now, instead of helping Danielle care for the new baby, Campbell must plan for their funerals. But first, she has to identify the remains of her 2-day-old granddaughter when they are recovered.

"I have to put my eyes on Kennedy to know she is gone," says Campbell.

The unthinkable tragedy came to light on Tuesday night, just after 11 p.m., when an officer with the Memphis Police Department was patrolling the area of Sedgwick Drive and East Levi Drive looking for possible stolen cars, the affidavit says.

While driving through the secluded area, which is just miles from Graceland, Elvis Presley's storied estate, he saw a tan Chevy Cruze on the side of the road with the driver's side window broken out.

After learning that the car was registered to Danielle, officers contacted her family, who said they hadn't heard from the new mother, who had left the house with the newborn, according to the affidavit.

At about 11:15 p.m., the officer who found the abandoned car found the body of a woman lying nearby that matched Danielle's description.

The victim suffered from multiple gunshots to her head and was declared dead at the scene, but her baby was gone.

Police issued a statewide Amber Alert for the newborn, whose car seat was found in a Walmart parking lot, CBS42 reports.

Authorities quickly zeroed in on Isabelle as a suspect, who admitted he lured Danielle to the secluded area of East Levi Drive and Sedgwick Drive, according to the affidavit of complaint.

He told police he shot Danielle in the head, leaving her on the side of the road, the affidavit alleges.

After being advised of his rights and waiving them, Isabelle then admitted to taking the newborn out of Danielle's car driving the baby to Island Park and the Upper Mud Island Boat Ramp in Whitehaven.

There, Isabelle "tossed the child into the water," the affidavit states.

Isabelle told police he took the weapon used to shoot Danielle in the head and threw it into the Mississippi River and the Wolf River Delta, the affidavit states.

Isabelle was arrested and charged with two counts of first-degree murder, murder in the perpetration of aggravated kidnapping, especially aggravated kidnapping, and tampering/fabricating with evidence, the affidavit says.

He remains held in jail as he awaits his next court date. It is unclear whether he has retained an attorney who can speak on his behalf.

Police continue to search for Kennedy, in what is now considered a recovery mission.

"Kennedy Hoyle has not been located; however, evidence suggests that she is deceased. The search will continue to recover her remains," authorities said in an update.

"Kennedy is a 2-day-old black female, 6 lbs., 17inches with brown hair and brown eyes," according to the National Center for Missing and Exploited Children, and "was last seen wearing a black and white polka dot onesie with pink pants."