A pastor's daughter, a pregnant mother and a boy of five were among the victims of the largest mass shooting in Texas state history, it emerged today.

Crystal Holcombe, who was eight months pregnant, was one the first names to emerge.

Daughters Emily and Megan had finished third and first in their respective categories in a 4-H bakeoff and displayed their handiwork in posted photos.

But on Sunday afternoon, her Facebook page went grim.

"Keep the Holcombe family in your prayers," a friend posted.

Crystal Holcombe was among the 26 killed by a lone gunman wielding an assault rifle, most as they worshipped at the First Baptist Church of Sutherland Springs, Texas, said her cousin, Nick Uhlig.

Uhlig told The Associated Press that Holcombe's in-laws were killed, and he told the Houston Chronicle that three of Holcombe's children also died.