A Penngrove couple facing possible prison sentences Thursday for abusing their 2-month-old daughter offered numerous explanations for the infant's condition, including that the mother accidentally sat on the baby, dropped her down the stairs and the family dog pounced on her.

Prosecutors said Jesus and Lyndsay Colula gave "bizarre and implausible stories" when confronted by detectives after the baby was discovered in May with a untreated broken leg, seven broken ribs and bruises all over her body.

Jesus Colula, 26, gave a half-dozen different accounts, including that his wife had "anger issues." Lyndsay Colula, 21, at one point blamed her husband's "culture" for failing to seek medical attention.

Neither accepted responsibility for what doctors described as "manhandling injuries" that caused "tremendous pain," inflicted by someone who must have known "exactly what occurred."

"What is clear is that neither defendant could keep their story straight," prosecutor Rosanne Darling said in a pre-sentencing brief. "And that is because the stories were built on a shameless foundation of deliberate and devious lies."

Darling is expected to ask a judge Thursday morning to sentence the pair to the maximum 12 years in prison. Each pleaded no contest in August to a single count of felony child abuse.

Jesus Colula remains in custody on an immigration hold. The mother is free on $65,000 bail.

Lyndsay Colula is seeking probation. In a letter to Judge Gary Medvigy, she said marijuana use prevented her from realizing the extent of her daughter's injuries. But she offered no further explanation.

She said she has given up custody of the baby and hopes to return to Sonoma State University, where she is a junior.

"Many terrible things happened to Natalia that I still do not fully understand," she wrote. "I truly apologize for that because I know that story sounds shaky."

The couple was arrested June 6, a few weeks after bringing their infant to a clinic for a "well baby" checkup. Doctors noticed swelling on the girl's shin and discovered through X-rays that the tibia had been fractured one to two weeks earlier.

When asked about the injury, the mother said she may have rolled over the baby in her sleep. Physicians rejected that story and the baby was taken away from the parents by Child Protective Services.

Further investigation by Sonoma County sheriff's detectives revealed the girl had many more injuries than originally detected. An examination at Children's Hospital Oakland showed healing fractures on seven ribs, a bruised ear and purple bruising on several toes that doctors concluded was likely the result of pinching.

Doctors said the ear injury was the result of "deliberate trauma" of some kind.

The baby's leg bone had been broken in half, in the middle, the results of a "direct blow or leveraging force." The parents apparently tried to mend it themselves by wrapping it in an Ace bandage, according to prosecutors.

The rib fractures happened about the same time, doctors said.

One doctor opined that the force required for such injuries would have to be violent and aggressive, such as a violent blow or squeezing.

"Based on the fact that the defendants both admitted being aware that the baby was injured ... it is hard to say that either of them was a passive participant or played a minor role in the crime," Darling said.