The incident happened at around 6.30pm on Thursday 6 September in Noel Street, Hyson Green.
A man aged between 30 and 35-years-old approached the boy and his mother.
Nottinghamshire Police have released a CCTV image of a man they want to speak to in connection with the incident.
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Fire crews say a large fire at the Zion Christian Centre in Halesowen was not started deliberately.
West Midlands weather: It will remain cloudy and wet overnight, with some heavier bursts of rain likely at times.
East Midlands weather: It will stay cloudy overnight with further outbreaks of rain, likely to turn heavy at times later.