A Phoenixville High School graduate, Henry was a theatre guild member in school and worked as a tax accountant, her Facebook profile shows.
"You were always kindhearted, wicked intelligent, stubborn, free-spirited, a portion of light that anyone could connect with and feel comfortable," said Steven M. Johnson, who is listed as Henry's brother on her page.
Henry's body was found and recovered by at least 11 rescue and dive teams around 3 p.m. near the area of Lock 60 in Upper Providence Township, local police said.
Witnesses apparently told police that they saw someone jump from the railroad trestle into the river.
However, Henry's cause and manner of death were determined to be an accidental drowning, the Montgomery County Coroner's Office told WFMZ.
Henry was among a group of 30 people who went out on the river for an annual tubing adventure, according to a Facebook post by Derek Wieneke.
Wieneke said he is in shock.
"It's hard, we thought you had gotten out with other people, we noticed you missing, damn it, Sam," he wrote.
He's hoping that a missing GoPro containing her final moments can be recovered from the river as a way to honor and remember her.
Meanwhile, more tributes flooded social media.
"My sister and confidant, not a soul has existed as tender and open and true as yours," wrote Alexa Michelle.
"I have marveled at the intricacies of your mind and the depths of your empathy, and I have never known a love like the love I felt from you," she added.
A celebration of life has been scheduled for 2 p.m. on Saturday, July 9 at her mom's house, loved ones said.
Stephanie Knapke Crowell has asked guests to bring something meaningful that reminds them of Henry.
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