The McCourty brothers, Devin and Jason, are one of just a handful of twins playing currently in the NFL. Born just 27 minutes apart (Devin is older), they attended Rutgers together, where they formed a formidable cornerback pair. Having redshirted, Devin entered the NFL in 2010 -- a year after his brother. He now starts for the Patriots, while Jason is a key part of the Titans defense.

It's safe to say that football runs in the blood of the Harbaugh family. Father Jack played collegiately at Bowling Green and went into coach after with notable stops in Iowa, Michigan, Stanford and Western Michigan. Jim played quarterback for the Bears, Colts, Ravens and Chargers before getting into coaching. Jim worked his way up from Raiders assistant to the University of San Diego, Stanford and now the 49ers. John played college ball at Miami University, started coaching at Western Michigan and was a long-time Eagles assistant coach prior to landing the job with the Ravens.

Packers LB Clay Matthews III is continuing a long football tradition in his family. His father, Clay Matthews, Jr., played 19 seasons for the Browns and Falcons, while his uncle, Bruce Matthews, was a Hall of Fame offensive lineman for the Oilers/Titans franchise from 1983 to 2001.

The 49ers' Ronnie Lott was arguably the greatest safety in NFL history. His son, Ryan Nece, made a nice career for himself as a linebacker in Tampa Bay.

Coaching runs in the Phillips family. Father Bum coached the Houston Oilers from 1975 to 1980, and son Wade most recently coached the Cowboys.

While Archie Manning never won a Super Bowl as QB of the New Orleans Saints, his sons Eli and Peyton have each won rings as quarterbacks of the Giants and Colts, respectively.

Both Bob Griese and son Brian played quarterback for the Miami Dolphins. Bob led Miami to nine winning seasons and a pair of Super Bowl victories in the 70s, while Brian started 83 games as quarterback for four different teams from 1998 to 2008.

Buddy Ryan made a name for himself as a defensive coordinator for the Vikings and Bears, then went on to coach the Philadelphia Eagles from 1986 to 1990. His sons, Rob and Rex, went on to become defensive coordinators as well. Rob recently moved from the Browns to the Cowboys, while Rex has since become head coach of the New York Jets.

Hall of Famer Howie Long spent 13 seasons as a tenacious defensive end for the Raiders. His son, Chris -- also a defensive end -- was drafted second overall by the St. Louis Rams in 2008.

Don Shula coached the Baltimore Colts from 1963 to 1969 and later won two Super Bowls as coach of the Miami Dolphins from 1970 to 1995. He passed on the coaching tradition to sons David, who coached the Bengals from 1992 to 1996, and Mike, who was the QB coach for the Jacksonville Jaguars before leaving for Carolina this year.

Kellen Winslow Sr. put together a Hall of Fame career as a tight end for the Chargers from 1979 to 1987, while his son, Bucs TE Kellen Winslow, Jr. is entering his sixth NFL season.

During his playing days from 1978 to 1991, Mosi Tatupu was one of the most popular members of the New England Patriots as a running back and special teams standout. His son, Lofa, has gone to three Pro Bowls as a linebacker for the Seattle Seahawks.

Former Giants QB Phil Simms was MVP of Super Bowl XXI. His son, Chris, has gone on to play quarterback for the Buccaneers, Titans and Broncos, starting 16 games.

Terry Robiskie played five seasons as a running back for the Raiders and Dolphins from 1977 to 1981. His son, Brian -- a wide receiver -- was drafted by the Browns in the second round in 2009.

Walter Payton was one of the most prolific running backs in NFL history. He played 13 seasons for the Bears and retired in 1987 as the NFL's all-time leader in rushing yards. His son, Jarrett, spent the 2005 season with the Titans and has spent three seasons in the CFL as a running back.

Kick returning runs in the Metcalf family. Father Terry spent six seasons in the NFL -- five with the St. Louis Cardinals -- as a dynamic return man and running back. His son, Eric, played for 13 seasons as a wide receiver/kick returner for seven different teams, including six seasons with the Browns.