The incident occurred about 40 kilometers west of Fort Worth.
Police say the mother and children were found dead, except for an 8-month-old infant. The baby was taken to a hospital and her condition is not clear.
The mother is believed to be separated from her husband.
The Parker County Sheriff said the deaths appear to be a murder-suicide, but an investigation is underway.
Names of the victims have not been released.
The incident has captured nationwide media attention.
In 2001, another Texas woman, Andrea Yates, drowned her four children in a bathtub. She was convicted of murder, but in 2005 a Texas court overturned the conviction. - VOA News
In 2004 A 35-year-old Texas woman, Dena Schlosser, was charged with murder after confessing to severing the arms of her 11-month-old daughter.
