Jack Thompson Granger and Amber Smith
During the discussion, Amber opens up about telling son Lincoln Monarch, 8, and daughter London, 10, that their brother had died after the accident, which they had witnessed. Lincoln was 5 and London was 7 at the time of the tragedy.
"We had to be very honest from the very beginning," Amber says. "We went home with that intention of being very honest ... We said, 'River was without oxygen for too long. They did everything that they could but Bubbie died.' "
"And then we let them process their emotions and told them that whatever they're feeling ... it's OK."
Amber says she and Granger allowed the kids to see them grieving as well. The couple also made the brave decision to share a lot of that experience on social media.
"So many times, it was not pretty ... sobbing tears, screaming in my car, punching my steering wheel, sitting by his bed, holding his blanket crying until nothing came out. That's where I was and that's what's real and I think people don't talk about [it]," she says.
"I was just trying to show the realness of pain and grief and it's not easy. It's OK to feel those emotions ... but you can't stay there, you can't stay stuck in that place."
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Granger and Amber Smith with their children River, London and Lincoln
Amber also discusses what it was like welcoming son Maverick Beckham, 9 months, after having lost River. "He's just the sweetest and just so happy," Amber shares. "Just bringing so much joy back into our lives."
The mom of four notes that she did experience some difficult times in the early weeks of postpartum.
"I was so grateful to have Maverick and I was so joyful, but I was also so sad that we didn't have Riv," she explains. "But then we wouldn't have Maverick if we hadn't lost Riv. It's a weird thing to think about."
Amber says that when she looks back at their journey, "there's grief and joy coexisting throughout these three years."
"It's looked like so many different things over the last three years. It has looked like anger and severe sadness and frustration and confusion," Amber says. "But it's also looked like growing through it and seeing joy in my other children and seeing them thrive in school, and bringing awareness to drowning prevention and helping others through the River Kelly Fund."
Amber says that she and Granger hope that by sharing their family's loss, people understand there is life and joy after unthinkable tragedy.
"I guess just being honest and vulnerable about that, that grief is messy and it's work but that there is light if you just keep taking the next step," she says. "And that's all we've been doing since that terrible day in June, is just doing the next thing and taking the next step forward to continue to live for our children and our marriage."
In May, Granger shared an Instagram video of baby Maverick floating in a pool by himself as part of his swim lessons.
"I never thought I would post something like this, but my mind is blown. This is a vid of our 8-month-old Maverick on his 10th ISR (infant swim rescue) lesson," the country singer wrote. "He's in full clothes and diaper. He can barely crawl, but now he knows how to hold his breath, twist his body, find the air, float on his back and cry. He can do this falling in head first, feet first or any orientation. He has the skills to float until help comes."
"He's a warrior and doesn't even realize it," Granger added. "He's an example for many families who see this video. Only ONE person needs to see this, and hear my plea to you. Drowning is the #1 accidental death of children age 4 and under. Thinking that adult supervision is enough is an absolutely DEADLY miscalculation. Hear me. I used to think that too."