Prosecutors have charged a Broken Arrow couple with child sexual abuse.
Deputies are also looking into whether the couple is involved in the death of another child.
Sheriff Chris Elliott said by all accounts, the Woolleys are a very tight-knit family.
"We've talked to all their neighbors, their neighbors are all very shocked," Elliot said.
A judge has decided Bill Woolley and his wife Lisa will stand trial.
Bill for child sexual abuse and Lisa for enabling child sexual abuse.
"We weren't able to stop this before it happened, because we didn't know about it," Elliot said.
Those counts involve a five-year-old relative.
Deputies are also investigating the death of that child's younger sibling who was found dead inside the home back in March.
"14-month-old babies just don't die … there's a reason why they die," Elliot said.
Elliott said a report from the medical examiner's office suggests the young toddler died by asphyxiation but the Woolleys deny knowing how that could've happened.
"We're operating under the pretenses right now that somebody inside that home murdered that child," Elliot said.
Elliott said they'll continue moving forward searching for justice for both children.
"Identify who's responsible inside that house for ending that child's life," Elliot said.
Sheriff Elliott said they'll continue investigating this horrific incident.