A 28-year-old Alvin man remained in jail Friday, charged with aggravated sexual assault of a child after officials said DNA tests confirmed he fathered a baby with his 11-year-old stepdaughter.

“In our office, there is a sense of deep sorrow,” said Lisa Jolly, executive director of the Brazoria County Alliance for Children, a nonprofit that provides a range of services to abused children. “To the general population, it is very shocking.”

The stepfather, whom the Houston Chronicle is not identifying because it indirectly could identify the victim, was arrested Wednesday and remained in the Brazoria County Jail in lieu of $200,000 bail Friday, the Brazoria County Sheriff's Office said.

If convicted of the first-degree felony child sex charge, the stepfather faces five to 99 years in prison. He works as a driver and does not have a criminal record, investigators said.

Sheriff's investigator Jeff Dandeneau said the man denied having sex with his stepdaughter and refused to provide a DNA sample.

Officials with Texas Child Protective Services said the 11-year-old and her 7-year-old sister were removed from the home in late November, about three weeks before she gave birth on Dec. 12. The girl's advanced pregnancy was noticed by teachers at her Alvin Independent School District elementary school in late September, and tests and medical examinations confirmed she was expecting.

“I can confirm we took her and her sibling into custody, and she is living with relatives,” said CPS spokeswoman Gwen Carter. “They're doing as best as can be expected. They're with some wonderful relatives who are protective and making sure they have everything they need.”

The young mother, her sister and the infant are living with an adult cousin, according to court papers.

Carter said the mother of the abused girl did not shield her daughter from the abuse, but she declined to elaborate.

“What I will tell you is, the child's mother was not protective, and that's why we went to court to take custody,” Carter said.

According to the probable cause affidavit filed with the charges, the 11-year-old told a relative that her stepfather had been having frequent sex with her since she was 6.

Dandeneau would not comment on whether the child's mother would face charges, saying any other charges would be decided by the district attorney's office.

Jolly said it would be very difficult to predict how the young mother will do in the future.

“It depends on the resiliency of the child, the support systems she has in place as far as someone encouraged her to obtain help,” Jolly said. “Our hope is she will receive all the support services she needs — legal, emotional and spiritual support from her family.”

james.pinkerton@chron.com