AURORA (CBS) — West suburban Aurora police were able to confirm Friday night that Timmothy Pitzen’s child car seat that was thought to have been missing from the vehicle driven by his mother, has been in the possession of Amy Fry Pitzen’s mother since before the pair went missing.

The grandmother took possession of the seat when she cared for the boy the week prior to Amy Fry Pitzen leaving with Timmothy. When the grandmother returned Timmothy to his home, she apparently forgot to return the child seat. The possibility that it was with the maternal grandmother was brought to the attention of investigators on Thursday night, but detectives were not able to talk with the grandmother until Friday night to confirm that fact.

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The boy’s Spider Man backpack, along with the toys and clothes purchased by his mother while they were in Wisconsin last week, are still not accounted for.

Timmothy Pitzen and Amy were apparently last together on Friday, May 13, in the Sterling/Rock Falls/Dixon area where Amy Fry-Pitzen made several cellular telephone calls. A multi-agency search for evidence in the I-88 and I-39 corridors in that area has come up empty.

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Police said they are increasingly concerned about Timmothy’s welfare because no one has heard from him since May 13 when he talked to a relative on his mother’s phone. He is about 4’2” and weighs around 70 pounds with brown hair and brown eyes.

Amy Fry-Pitzen’s body was discovered on May 14 in a Rockford motel after she committed suicide. There was no sign that Timmothy was ever with his mother when she checked into the motel late Friday night or when she was in a Winnebago, Ill., food store about three hours before she checked into the motel.

Anyone who believes they saw either the boy, his mother, and/or anyone who may have been with them — or anyone who may have information on the case — is asked to call Aurora Police at (630) 256-5500, or their local authorities by dialing 911.

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