Santiago Calatrava
Santiago Calatrava is a world-reknowned architect who gave the (reportedly unintelligible) SEAS Class Day speech and received an honorary degree at Commencement in 2007.
Calatrava is also a Columbia parent. His son Gabriel earned a BS in Civil Engineering in 2007. His son Michael also earned a BS in Civil Engineering, in 2006, and an MS in the same subject in 2007, and will be going on to the PhD program in that discipline.
The elder Calatrava however, has yet to design a building for Columbia.