The tot who was found today around 1:30 p.m. at Lake Shore Boulevard West and Twelfth Street had no clothes on.
Police said the child is currently at 22 Division, and the mother is also at the station.
There was no signs of injury or distress to the boy, but police are seeking medical care as a precaution.
Elijah Marsh left the lowrise apartment building where he was staying on Thursday at around 4 a.m. and was later found without vital signs. He was pronounced dead in hospital a few hours later.
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