Lyric Cook, 10, and her 8-year-old cousin Elizabeth Collins disappeared on Friday when they left on a bike ride at their grandmothers house. The girls’ bike’s and a purse were found near Meyers Lake hours after they were reported missing.

The aunt of the two missing Iowa cousins said Thursday that authorities have accused a family member of involvement with the girls’ disappearance.

Black Hawk County Chief Deputy Rick Abben said Thursday that authorities expect 100 percent cooperation from Misty and Dan Morrissey, parents of 10-year-old Lyric Cook-Morrissey.

Both parent’s have extensive criminal record’s.

The family is saying that they all are cooperating, and are willing to take polygraph tests.

“We just want our girls home,” Tammy Brousseau, an aunt to both girls, told CNN’s “AC360?.” ”We’re bracing for the worst but hoping for the best.”

FBI divers have been called in to search Meyers Lake. FBI spokeswoman Sandy Breault said that if the divers are deployed, they would search the deeper holes of water in the lake, which may be as deep as 20 feet, she said.

On Monday, authorities began draining the lake, a saying it could take up to three days.

The mother said ”They don’t swim there. My daughter is familiar with swimming in lakes, so I don’t think she would be scared of this lake, but they don’t come here and swim here,” she said. “Because we haven’t found them anywhere in the surrounding area, I feel like maybe they were taken.”
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