HARRISONVILLE (Missouri) - THE older sister of a girl allegedly molested and impregnated four times by their father said on Thursday their mother allowed the abuse and should face more than a child-endangerment charge.

'I want her to get more charges,' the 20-year-old said outside a western Missouri courthouse. 'I want her to pay as much as my father. I don't want either of them to get away with a slap on the wrist.'

The mother is charged with one count of endangering the welfare of a child. Cass County prosecutors said additional charges were possible but declined to elaborate. The woman is free on US$10,000 (S$15,000) bond.

The Associated Press is withholding the names of the suspects and other family members to protect the identity of the daughter who was allegedly sexually assaulted. A judge entered not guilty pleas on behalf of the mother and father during their initial court appearances, prosecutors said.

The 47-year-old mother was allowed to miss a scheduled court appearance Thursday; a preliminary hearing was set for March 5. Her public defender, Angela Weatherford, declined to comment on the case.

Her husband, also 47, faces charges including second-degree murder in the death of a boy born in November 2006. The infant is believed to have died months later after not receiving medical treatment for pneumonia.

The baby's remains were found last month in a cooler on a rural property where the family once lived near Harrisonville, a town of about 9,000 people about 60km south of Kansas City.

Two other babies the man is suspected of fathering with his now 19-year-old daughter also died. Charges have not been filed in those cases.

The body of one of those babies was found in a different cooler last month on the Harrisonville property. The other infant is believed to have been buried in Oklahoma, where the family briefly lived.

A surviving child - a 3-year-old boy - is in state custody.

The man also is charged with endangering the welfare of a child, statutory rape and two counts each of incest and abandoning a corpse. He is being held on US$500,000 bond.

Family members and investigators have said the daughter who had the babies was 13 when the molestation started. She has not been charged with any crime. -- AP