In the video, titled ‘POV: You forgot it’s Juneteenth – No work today!’, she could be seen groggily getting out of bed and leaving the house before returning with a bottle of wine and snuggling down on her couch.
The irony of her celebrating the public holiday just hours before her death has not been lost on her fans.
The clip racked up more than 3.8 million views and 16,400 comments in a day, as followers shared their grief at her passing.
“It’s so crazy how fast a life can change,” wrote one. “RIP.”
Britney’s sister Tiffany Smith Cofield told local news outlet ABC13 that she’d been on her way home when she was met by the terrible scene of the crash.
"It looked like her car and everybody, when I was walking up, said a mom and daughter died,” she explained. “I knew they had left and knew the only mom and daughter would be my mom and sister.”
"There will never be a time when I won't miss my mother and my sister,” Tiffany added. “They were my best friends. They were everything.”
Britney (left) and her mum Sherie were killed on their way to a Juneteenth celebrationTiffany Smith Cofield/GoFundMe
She has since set up a GoFundMe page to raise money for Britney and Sherie’s funeral.
In a blurb to the fundraiser, she wrote: “My mom and sister were tragically taken away from us way too soon in an accident involving a reckless driver in Houston. This was just as my sister, beloved TikToker Britney Joy, began rising up in fame for her 9-5 videos that hit the internet by storm. Everyone related to her stories and those of her characters.
“Unfortunately, we were not adequately prepared to have to lay both my sister and mother to rest at the same time. This happened so suddenly and was truly something I could have never imagine [sic]. Losing my best friends.”
At the time of writing, more than $63,000 (£49,500) had been raised.
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