Colorado mother Shanann Watts returned from a work trip early Monday excited for what was to come.
On Instagram, before she headed to Arizona for business, she had rattled off the highlights of a bustling month — and one of the things she was looking forward to was a sex reveal party for her third child.
Once she made it home to Frederick, however, Shanann met a grimmer fate: Authorities believe the 34-year-old was murdered by her husband, Chris Watts — likely in the house they shared with their young daughters, Bella and Celeste, who were also killed.
The trio were reported missing on Monday afternoon, about 12 hours after Shanann got back from Scottsdale. Her body was found Thursday and the remains of her girls are believed to have been recovered later that same day.
A friend told local TV station KDVR that this coming Saturday was the scheduled day for the 15-weeks-pregnant Shanann’s sex reveal party, to be held at the family’s home in Frederick.
“I’m completely at a loss for words,” Ashley Bell told the outlet.
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Shanann’s younger brother, Frankie Rzucek, previously said she was going to give birth to a son named Nico.
While he initially blasted his brother-in-law — describing Chris, 33, as a “heartless psychopath” — on Friday he posted again about the killings, this time to grieve.
“I’ve never been so mad, sad, enraged, hurt heartbroken, lost, and shocked in all my life,” Rzucek wrote. “So forgive me for how I went about it. My sister and nieces meant the absolute world to me. They made me strive to be an even better man. I wanted them to be proud of their Uncle.”
Chris, who was arrested Wednesday night before the bodies of his wife and kids were found the next day, remains in custody without body and is accused of first-degree murder and three-counts of tampering with a body.
His attorney did not respond to PEOPLE’s request for comment.