Man sentenced 200 years for impregnating his 11-year-old granddaughter...

A grandfather has been sentenced to 200 years in prison for impregnating his 11-year-old granddaughter and sexually assaulting the girl's younger sister.

District Judge Jeffrey Langton sentenced the 55-year-old Stevensville man on Wednesday to 100 years each on two counts of incest.

The judge said that he seemed 'to lack any semblance of a conscience'.

The man, who is married according to public records, has not been identified to avoid identifying the victims.

The man was arrested in June after the 11-year-old girl was found to be 32 weeks pregnant.

She had gone to the doctor with cramping and claimed to have had sex with a 14-year-old boy at a county fair, whose name she did not know.

However, medical staff noted that the term of the pregnancy and girl's suggested date of conception were out by three months.

During a later interview, the girl then admitted that her grandfather had told her to make the story up.

The 11-year-old said she did not know she was pregnant until informed by a doctor 'because she didn't know what pregnant felt like'.

On July 1 last year, the nine-year-old girl told her biological mother that she witnessed the pedophile come into the girl's bedroom and assault her sister with his hands and mouth.

During a forensic interview, she gave a detailed account of the oral sex, The Missoulian reported.

Father impregnates daughter 2

The younger girl also told investigators that he had sexually assaulted her by 'kissing her privates', then telling her it was a secret she had to keep.

The 11-year-old victim gave birth in August. The grandfather was the guardian of both girls.

The man pleaded guilty in November and bowed his head as he briefly apologized before his sentencing.

He would have to serve 50 years in prison before being eligible for parole, at the age of 105.

The pedophile had been charged two decades ago with lewd conduct with a minor and forced sexual penetration in a different state.

The sheriff's office is still investigating claims that he sexually assaulted other girls, one as young as three.