Phil Mickelson could play in the U.S. Open, and his daughter certainly would have understood. Amanda Mickelson spent her childhood accustomed to her father leaving home for weeks at a time while he competed on the PGA Tour. She's well aware a win would complete his career grand slam.
Mickelson is planning to skip the Open this year because it's less important than Amanda's graduation from high school. The same baby who kept Mickelson on call in 1999, when he lost to Payne Stewart, is weeks from her 18th birthday and scheduled to give the commencement address.
The best thing about Mickelson's decision was that it really wasn't a decision. It was a no-brainer. You only get one chance to witness certain moments of your children's lives. People who make their living in professional sports have missed more moments than they would rather admit.
Mickelson put his family first, a decision made easier based on millions of dollars he earned on tour. If he never wins a U.S. Open, he's not going to waste time thinking about the year he missed. But he would have forever regretted skipping his daughter's graduation so he could play golf.