The children are members of a Charleston, South Carolina, family that was visiting relatives when the storm hit.
UPPER MAKEFIELD TWP., Pennsylvania (WPVI) -- After fatal flood waters swept through the Bucks County, Pennsylvania area over the weekend, communities are deep in mourning.
The severe flooding led to the death of five people and the waters swept away two small children who are still missing as of Thursday.
The Crossing Church in Upper Makefield Township served as a command center for first responders while they searched for the kids.
Weather conditions have been hampering the efforts, but Upper Makefield Township police said that crews were going to continue the search for 2-year-old Matilda Sheils and her 9-month-old brother Conrad Sheils on Friday.
SEE ALSO: Effort to find 2 children lost in Bucks flash flood experiences 'setback' due to weather: Police
The children are members of a Charleston, South Carolina, family that was visiting relatives and friends when they got hit by a "wall of water," officials said.
Upper Makefield Fire Chief Tim Brewer said the children's father, Jim Sheils, grabbed their 4-year-old son, while the children's mother, Katie Seley, and a grandmother grabbed the other children.
Sheils and his son made it to safety, but Seley and the grandmother were swept away.
The grandmother survived, but Seley was among the five people who drowned, according to the Bucks County Coroner's office.
On Thursday night, the church did not serve as a command center. Instead, it held a prayer vigil for those who lost their lives in the flooding.
The church's pastor said it was a safe space to reflect on the tragedy and grieve as a community.
"I know many of us in this room today are wrestling with why. Why did this happen? Why them? Why now?" said Lead Pastor George Matthew Clash.
Dozens gathered at the church around 7 p.m. to mourn and honor the people lost during the devastating weather.
Resident Jaime Sosonkin had a front-row seat at the vigil and said she was deeply moved.
"I just feel so grateful. I mean, literally, so many people lost their lives and no one knows what to do in that situation. I didn't know what to do," said Sosonkin.
She said she was thankful to be alive, as she was caught in the flood waters while only eight minutes away from her home.
"The current took me and I just kept praying, I kept praying my husband and son wouldn't find me drowned," she said. "I kept getting thrown underwater and couldn't breathe."
Sosonkin survived by holding onto a tree for hours along with another teenager who had been swept away.
SEE ALSO: Families, friends remember those lost in Bucks County flash flooding
Those killed in the storm were Enzo De Piero, 78, and Linda De Piero, 74, of Newtown; Yuko Love, 64, of Newtown; Katie Seley of Charleston, South Carolina; and Susan Barnhart, 53, of Titusville, New Jersey.
During the service, the pastor also took a moment to thank all the first responders who were working diligently to find the two small children.