As students hid behind desks and doors during the latest deadly school shooting in the United States, they pulled out their cell phones.
It was just before 10:30 a.m. Wednesday, that Becky Van Der Walt received a text message from her son that no parent wants to receive.
"I think there's a school shooting," Van Der Walt's son, Henry, a junior at Apalachee High School in Winder, Georgia, wrote, according to text messages shared with ABC News. "We heard gunshots and the police shouting ... We're all in hard lockdown."
Around eight minutes later, Henry sent another text to his mom with three simple words, "I love you."
Around the same time Wednesday, Erin Clark, also a parent of an Apalachee High School student, saw a concerning text message pop up on her phone from her son, Ethan.
"School shooting rn .. i'm scared," Ethan, the high school student, wrote to his mom. "pls i'm not joking."
When Clark responded that she was leaving work, Ethan, too, responded with just three words: " I love you."
Sonya Turner was home for less than an hour Wednesday after dropping off her 15-year-old daughter at Apalachee High School when she too got a worrisome text.
"There's a real lockdown," Turner's daughter Abby, a sophomore, wrote to her mom from biology class. "idk how to explain it ... i heard shots but i don't anymore."
'I had so much fear': Students recount shooting at Georgia's Apalachee High SchoolWhile Abby and her fellow classmates were texting their parents Wednesday morning, not knowing what would happen, a 14-year-old student had allegedly opened fire at Apalachee High, killing four people and injuring nine.
The 14-year-old student accused of opening fire at the school has been charged with four counts of felony murder, with additional charges expected, Georgia Bureau of Investigation officials said Thursday. A motive is not known.
Two teachers and two students were killed in the shooting: math teacher and football coach Richard Aspinwall, 39; math teacher Cristina Irimie, 53; and students Mason Schermerhorn, 14, and Christian Angulo, 14, according to officials.
Eight students and one teacher were injured, officials said, but all are expected to survive.
Becky Van Der Walt told ABC News it was "terrifying" to receive a text message about a school shooting from her son, with whom she reunited later in the day.
Ethan Clark also survived the shooting, as did Turner's two daughters, Abby and Isabella, a 14-year-old freshman at Apalachee High.
Turner told ABC News that as soon as texts from her daughters about gunshots came in just before 10:30 a.m., she called her husband to go to the school, telling him, "It's real. Go. Go. Go.'"
For the next hour, Turner, also the mom of a 9-year-old son, said she stayed glued to her phone, keeping her daughters calm, making sure they had safe places to hide and praying with them.
"Where are you hiding," Turner asks in one text message, with Abby responding, "I'm behind a long desk."
"Is there an additional closet or anything you can get in," Turner asks Abby in a later message.
"No I can't move ... I'm not aloud to mo[v]e," Abby replies, leading Turner to tell her, "Ok. Pray ...," while also texting prayers.
In another message, Turner asks her daughters to simply keep communicating with her so she knows they're alive, writing to them, "Keep talking to me."
Isabella, just a few weeks into her first year of high school, texted her mom, "I love you. Mommy im scared."
Grief counselors from Columbine, Parkland, Sandy Hook describe what happens after a school shootingTurner said over the course of the morning, she received text messages not only from her daughters inside the school, but from fellow parents who were also communicating with their kids and helping each other as they intermittently lost communication.
"[A friend] has two kids [at Apalachee High School], and she couldn't get one of them on the phone, and he turned out to be in the classroom of the first teacher that was pronounced dead," Turner said. "She's texting and texting and couldn't get him and couldn't get him, and that's because he was trying to save his teacher."
In another instance, Turner said she temporarily lost communication with Isabella.
"That was a total freak-out moment but her phone had gotten taken, the whole class, they took their phones," Turner said, adding. "But when they ushered them all out onto the football field, she got to a friend who was able to text me ... so I knew she was safe."
Turner, who is recovering from abdominal surgery, said she ended up walking over one mile from her home to the high school, where, after several hours, she was able to reunite with her daughters.
"Abby just keeps hearing the gunshots, and their question now is, how do we go back to school," Turner said. "Izzy’s stuff is all in her classroom right where she left it, and she’s like, ‘Mommy, I don’t want to go get it. I don’t want to go back into that room.’'
ABC News' Caroline Guthrie contributed to this report.