Officials said Lena Mock Knight, 65, Jennifer Mock, 58, and Mock's grandson Wyatt Smith, 8 months, were pulled from the burning building by a a state trooper and a telephone company worker.
All three victims were taken to hospital and were listed in "very critical condition" with burns and other injuries as of Tuesday afternoon, said Montgomery County Fire Marshal Jimmy Williams. The two women were transported by helicopter to Memorial Hermann Hospital in Houston, and the infant is being treated at University of Texas Medical Branch in Galveston.
Family members said the stove's propane tank had been filled Monday and may have been leaking.
Other homes surrounding the explosion site were also damaged, with windows blown out and trees knocked down. The blast could be felt as much as five miles away, said Grimes County Sheriff Don Sowell.