Serena Williams has won four straight majors for the second time in her career. In three weeks, she will start her quest in Queens to win her first calendar grand slam and her fourth straight U.S. Open title.

Williams, who turns 34 in September, could easily lock in her focus on tennis. Instead, she is doing what her and her family has done for the past two decades: Fight for social justice.

Christian Taylor, an African-American football player at Division II Angelo State was shot and killed Friday in Arlington, Texas. Police responded to a burglary call at a car dealership and confronted Taylor, taking his life.

A police statement read: "As officers confronted the suspect, there was an altercation during which at least one officer discharged his weapon. The suspect was pronounced dead at the scene. Investigators have determined that the suspect had no weapon."

Williams responded:

The shooting came nearly one year to the day AFTER Darren Wilson's fatal shooting of Michael Brown on Aug. 9, 2014. When Wilson was not indicted in the Ferguson, Mo., shooting last November, Williams reacted:

For the Williams family, gun control is an issue very close to home, as Serena's half-sister, Yetunde, was shot and killed in a 2003 confrontation in Compton, Calif. Serena was born in Saginaw, Mich., but she spent much of her childhood in Compton. For Serena, the "Straight Outta Compton" meme that was popularized last week is more real than for others. It is literal.

#StraightOuttaCompton @beatsbydre

A photo posted by Serena Williams (@serenawilliams) on

Williams is enjoying what might be the best season of her career. Along with her three major championships, Williams is 40-1 on the season. Her one loss came to Petra Kvitova in May.

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-- Follow Jeffrey Eisenband on Twitter @JeffEisenband.