Skyhawk 172/Cutlass 172
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 5
Workload; Situational Awareness; Distraction; Confusion
ATC Issue All Types; Conflict NMAC
Flight Crew Requested ATC Assistance / Clarification
Human Factors
Aircraft X was on departure for Runway XXR traffic pattern. Once I had runway spacing between two category 1 aircraft I cleared Aircraft Y for takeoff in the traffic pattern for Runway XXR. Aircraft X upwind was unusually further than expected. As I was attempting to request an IFR release for an air carrier off of Runway XY I noticed that Aircraft X had made a slightly earlier than expected cross wind turn at a higher altitude than normal. I issued a traffic call to Aircraft Y; and that is when a transmission with no call sign said 'they almost hit us' I had visual on both aircraft and continued to separate both aircraft in the downwind.  I could have initially notified the following aircraft (Aircraft Y) of the proceeding aircraft's intentions; and let know my intention to have aircraft follow in the traffic pattern.
A Tower Local Controller reported a departing VFR aircraft reported a NMAC with a preceding departure.