When Fin finds Austin in the kitchen of the daycare, the actor playing the baby is big enough that his head is above the shell of the car seat. When the car seat gets moved, there is clearly a doll inside the car seat instead of a live baby. The doll is at least 8-10 inches shorter than the live baby, and is closer to the size of a newborn. Then there is suddenly a live baby in the car seat again.
While talking to Cragen abut an 5 year old undercover case evolving Sandra Knowles daughter Tricia Knowles. Odafin says Tricia was an 18 year old runaway that didn't want to go home who had a bad coke addiction. When he shows her ID to Cragen it says Tricia Knowles DOB i 7-14-87 and the ID expires on 7/04 which would be around Tricia's 17th birthday. The case is based around Nov/Dec '04. According to Tricia's ID when she and Odafin met she would have been 11 or 12 not 18. For Tricia to be 18 in '99 when she and Odafin would have crossed paths she would have had to be born in '81.