Granger Smith's wife, Amber, is opening up about how the dynamics of motherhood have changed since the couple's youngest son, River, died on June 6.

River Kelly Smith turned 3 a few weeks before he drowned in the family's backyard pool, and Amber admits it's been a struggle to find a new normal in the weeks since. She says she has "this pit in my stomach constantly," but that she's noticing signs of little River everywhere she looks.

The family — Amber, Granger, 7-year-old daughter London and 5-year-old son Lincoln were in Chicago over the weekend while Dad played Windy City LakeShake Festival, and they made a visit to the city's Field Museum to see dinosaur bones while there.

Granger Smith's Tribute to His Late Son Is So Touching and Emotional

"We just happened to be in the same city as the 'biiiigggggggest T-Rex' ever found. We had to make a trip to see it in honor of River," Amber writes on Instagram with a photo of the kids, also noting that the dino, Sue, was discovered in the city of Faith and died by a river.

"Open your eyes and you will see signs all around you. We think just maybe, Riv is having the best time of his life in Heaven with this," she adds.

She acknowledges that getting back into everyday life and back on the road while Granger is touring has not been easy without River, and that everything is a reminder of him. "All I can think about is how he would love exploring and seeing all that we are seeing. I see his name everywhere, I see little red-headed toddlers everywhere. I miss his silly personality and his bright light," she says.

"I have this pit in my stomach constantly, because I’m trying to make life as normal as possible for our other 2 incredible kiddos, London and Lincoln, while hurting so bad inside," Amber continues. "I look around at everyone else and wonder if anyone is going through something like we are. Dumb little things don’t matter anymore. My family does. My faith does. We’ve got this, because God’s got us."

After River's death, the family and Smith's Yee Yee Clothing brand launched a T-shirt benefitting Dell Children's Medical Center in Austin, Texas, where River was treated after the accident. The shirts — which are red, his favorite color, and feature an excavator — have raised $218,791 for the hospital.

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