WATERLOO, Iowa (AP) — The parents of two missing Iowa cousins have prepared an open letter to whoever abducted the girls, asking for the children to be freed.

It’s been four months since 11-year-old Lyric Cook and 9-year-old Elizabeth Collins were last seen riding their bicycles near a lake in Evansdale. The girls have had birthdays since then. Authorities believe the girls were abducted.

The parents submitted their letter to the Waterloo-Cedar Falls Courier. The Courier reports Heather Collins composed the letter, which was then signed by her husband Drew Collins and Lyric’s parents, Daniel Morrissey and Misty Morrissey.

The letter published in the paper Tuesday says “taking the girls from us has caused much pain: pain for them, pain for us and our families. We want you to know that we are praying for you to do the right thing.”

Heather Collins said she drew on thoughts she had posted earlier on Facebook in composing the letter. She hopes the letter could prompt the person who abducted the girls to release them, maybe in an area where he or she wouldn’t be seen.

“They can still drop them off at a park or wherever and still not be seen, because our desire is not to know them. Our desire is to get the girls back, and that is all we want… The kids can be dropped off at a park, and they can get to a house,” Heather Collins told the Courier.

The letter notes that someone who abducted the girls must not have received the love needed when growing up. “Because only someone who hurts inside would hurt another person and their family.”

The letter ends with a plea for the abductor to let the girls go.

“Do the right thing. Be a hero,” the letter implores.

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