Janelle Brown is paying tribute to her late son Robert "Garrison" Brown on what would've been his 26th birthday.

"Happy Birthday Sweetheart," the Sister Wives star wrote on Instagram April 10 alongside a video featuring throwback footage of his birthday celebrations from over the years. "We are missing you terribly today. It's hard to believe you aren't here anymore." 

Janelle also shared how she and her loved ones honored Garrison, who was one of her six children with ex Kody Brown, on the day.

"We talked a lot about you today," she continued, "and even went to Texas Roadhouse for dinner (your favorite place)."

And while he's gone, the 54-year-old noted he will forever be in her heart.  

"I still feel you nearby sometimes," she added. "And I'm grateful we will see each other again when my journey is completed."

Janelle wasn't the only one to mark the day with a heartfelt message. Garrison's brother Hunter Brown reshared a 2020 birthday post on his Instagram Stories and wrote "Happy birthday my dude!" In addition, their sister Madison Brush reshared their mom's tribute and wrote, "Happy Birthday, Carebear. Miss you dearly."

Garrison was found dead at a home in Arizona on March 5, the Flagstaff police confirmed to NBC News. Though an official cause of death has yet to be shared, the police noted to the outlet that it appears he died by suicide.

Following the death of Garrison—who was one of Kody's 18 children from his plural marriages to now-exes Janelle, Meri Brown, Christine Brown and wife Robyn Brown—several family members shared how they're carrying on his legacy and how they're navigating grief. 

For instance, earlier this month, Meri came across an old photo of her and Garrison on her phone that she didn't know she had but is one she "will forever cherish." 

"Seeing it immediately moved me to tears, a testament of the love I have for him, the pain of the loss of him," she wrote on Instagram April 3. "It's a reminder that grief comes in unexpected waves, memories of the moments with him all that remains. Four weeks today without him here with us. A lifetime of memories to hold sacred."

To learn more about the Brown family, keep reading.

Born May 21, 1994, Logan is the oldest son of Kody Brown and Janelle Brown. He is also the eldest child of 18 in Kody's entire brood.

After graduating with a master's degree in business administration from the University of Nevada in 2020, he married Michelle Petty two years later.

Aspyn is the oldest child of Kody and Christine Brown. She was born on March 14, 1995.

Also a University of Nevada alum, Aspyn tied the knot with Mitch Thompson in 2018. 

Born on July 29, 1995, Leon is the only child of Kody and Meri Brown.

In 2020, Leon came out as transgender, sharing that they were previously "socialized as a girl."

"I was pretty young & unfortunately i grew up in a context that was incredibly gendered & restrictive," Leon—who also goes by "Leo"—wrote on Instagram. "and here’s the thing, i’m finally ready to share my favorite self with the world. and that self is incredibly genderqueer, trans, and unapologetic."

Leon married Audrey Kiss in 2020 at a Colorado courthouse wedding.

The second of Kody and Christine's children, Mykelti was born on June 9, 1996.

She married Antonio "Tony" Padron in 2016 in a wedding ceremony documented on Sister Wives. The couple are parents to daughter Avalon and twin sons Archer and Ace.

Janelle gave birth to Madison—her second child with Kody—on Nov. 3, 1995.

After studying at Utah State University, Madison married Caleb Brush in 2016. The pair share kids Axel, Evangalynn and Josephine.

Janelle and Kody welcomed Hunter—their third child together—on Feb. 9, 1997.

Hunter graduated from the United States Air Force Academy in 2020, before studying nursing at Johns Hopkins University.

Kristine gave birth to her and Kody's third child together on Aug. 7, 1998.

Born Oct. 31, 1998, Garrison was Kody and Janelle's third youngest child together. He died on March 5, 2024 at age 25.

Dayton is the oldest child of Kody's fourth wife Robyn Brown from her past marriage with Preston Jessop. He was adopted into the family in 2015, five years after Robyn spiritually married Kody.

In 2014, Kody legally divorced his first wife Meri so he could marry Robyn and officially adopt Dayton as his son. 

Nicknamed Gabe, the fifth child of Kody and Janelle was born on Oct. 11, 2001. 

Kody and Christine welcomed their fourth child on Oct. 15, 2001.

Gwendlyn tied the knot with Beatriz Queiroz in 2023.

Aurora is the second oldest child of Robyn. She was legally adopted by Kody in 2015 after he married Robyn the prior year.

Kody and Christine welcomed their fifth child together on June 13, 2003.

Her struggles with scoliosis have been documented on Sister Wives.

Breanna is Robyn's third child from her marriage to Preston. After Robyn married Kody, Breanna and her older siblings were legally adopted into the family.

Kody and Janelle welcomed their youngest child together on Dec. 7, 2004. The exes reunited for Savanah's high school graduation in 2023. 

Born on April 13, 2010, Truely is the youngest child of Kody and Christine.

Kody and Robyn welcomed their second youngest son on Oct. 27, 2011.

Born on Jan. 10, 2016, Ariella is the youngest daughter of Kody and Robyn. She is also the youngest child of 18 in the entire Brown family.

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If you or someone you know needs help, call 988 to reach the Suicide and Crisis Lifeline. You can also call the network, previously known as the National Suicide Prevention Lifeline, at 800-273-8255, text HOME to 741741 or visit SpeakingOfSuicide.com/resources for additional resources.