The head basketball coach of the University of California Berkeley women’s team had an encounter with a Southwest Airlines employee. Lindsay Gottlieb was asked to provide documentation establishing maternity to her 1-year-old son. Lindsay provided the child’s passport to the gate agent as proof of maternity. The gate agent then asked for a Facebook post to demonstrate Lindsay was the mother of the bi-racial child.

Lindsay was confused about how a passport wasn’t sufficient. Lindsay surmises that it was because her son has a different last name and is a different race.

She complained on Twitter that she has flown over 50 times with her 1-year-old son and it hasn’t ever been an issue until now.

Southwest Airlines is investigating the incident.