And here's the crazy part: The Man and The Kid share the same birthplace of Donora, Pa., 25 miles south of Pittsburgh on the Monongahela River. Those must be some magical waters, having produced not only Musial and Junior, but also Ken Griffey Sr., another wonderful player in the generation bridging Musial and Junior.
Donora, a coal-mining, steel-producing borough, contained 13,180 citizens in 1941, when Musial began his big league career at 20. The town's population had fallen to 5,653 in the 2000 census, reflecting hard times. But Donora and nearby communities are hopeful that the natural gas industry will lift and renew the region.
Lift and renew are what the birthday duo, Musial and Griffey, have done to their sport over the courses of their brilliant careers.
Though separated by a half-century in age, Stan the Man and The Kid are essentially the same personality -- light-hearted and fun-loving in nature. Both men played the game from the heart, with passion, all the while keeping a smile on their face and an upbeat bounce in their step.
If you were a Musial fan in the 1940s, '50s and '60s, you had to be a Griffey fan in the '80s, '90s and 2000s.
The swing from the left side of the plate by both men was positively lyrical. Musial had that unusual crouch, uncoiling to drill line drives all over the field, while Griffey's gorgeous uppercut launched missiles to distant places.
Musial retired in 1963 as the National League's all-time hit leader. He was eventually run down by Henry Aaron and Pete Rose and now ranks fourth in history with his 3,630 hits across 22 seasons.
Griffey's majestic swing produced 630 home runs, sixth in history.
Musial is sixth all time in RBIs and ninth in runs scored. Griffey stands 15th and 33rd, respectively.
Nobody ever was more consistent than The Man. A three-time NL Most Valuable Player Award winner, he placed in the top 10 in the balloting 14 times. He was the NL leader in OPS seven times, the runs created king nine times.
The modern metrics compute Musial's career WAR (wins above replacement player) at 123.4 -- higher than Ted Williams, Lou Gehrig and Mickey Mantle.
Across Musial's career span, the only superior player in his league was Willie Mays, whose all-around game went to a level previously unvisited in the national pastime.
While Musial attacked the game, Griffey Jr. was as graceful and gifted as anyone who ever played the game. Much like Aaron, Junior's easy manner and gliding style masked a burning desire to beat you with all five of his tools.
There are those who will argue on statistical merit for Barry Bonds, but Griffey was the Player of the Decade while with the Mariners in the 1990s. He won 10 consecutive Rawlings Gold Gloves in center -- Bonds stayed in left -- while hitting 40 or more homers six times and driving in at least 100 runs seven times. He won the 1997 American League MVP Award with 56 homers and 147 RBIs.
Retiring in 2010 as a Mariner after nine seasons with the Reds and one with the White Sox, Griffey had 1,836 RBIs to go with the 630 homers, scoring 1,662 runs. His career OPS was .907. His WAR of 79.2 surpassed those of Joe DiMaggio, Rose and Johnny Bench.
The Kid, son of one of the Big Red Machine's stars in Cincinnati, could have put up even more amazing career numbers if he'd charged into fewer walls while pursuing home runs and extra-base hits.
Like Musial, Griffey played 22 seasons. But injuries reduced five of those seasons to 83 or fewer games -- including his age 32-34 seasons with the Reds.
Conserving himself physically, as Bonds did in left, Griffey could have been the one to eclipse Aaron's home run record. Junior's power was electric from the beginning.
At age 30, Griffey had 438 home runs, Bonds 292. Bonds, who came to Pittsburgh from Arizona State, got a later start, but through 12 seasons, he had 64 fewer homers than Griffey.
Musial was third "M" of the Greatest Generation, joining Mays and Mantle.
In St. Louis, there was No. 6, and there was everyone else. Mark McGwire smashed homer records and Albert Pujols put up historic numbers for the Redbirds, but both men would tell you in a heartbeat that there's only one Man in the Cardinal Nation -- and that is Musial.
The game has had no kinder, gentler ambassador than the harmonica-playing, story-telling gentleman from Donora who did nothing but enrich his sport and society.
Happy birthday, Stan. You too, Junior. Donora should be proud.
Lyle Spencer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.