If a downstream job is called by two different upstream jobs, the last run upstream job is the only one that shows the Build Flow graph .  The other upstream job does not show the build flow unless it is run again, even if other past job runs are listed in Jenkins.

Steps to reproduce:

1. Create a downstream job.
2. Create two different upstream jobs that call the downstream job.
3. Run the first upstream job.
4. Once the first upstream job completes, run the second upstream job.
5. The first upstream job will not show the Build Flow.  Only the second upstream job will show the Build Flow.