As an only child, I’ve spent a great deal of my life thinking about what growing up with siblings would have been like. There are no doubt plusses and minuses, and most people with siblings probably did just as much daydreaming about life as an only child. I was a sports-obsessed kid with very limited athletic ability, and as it became more and more obvious that my baseball and basketball careers would be coming to an end around age 16 part of my natural coping process was convincing myself that not having a brother to constantly compete against held me back.

Now that I’m a sports-obsessed 33-year-old with very limited athletic ability, I’m fairly certain that any brother I had would have been similarly mediocre, but there’s a sliver of hope that lives in the unknown. One of my best friends growing up was a good basketball player—a quick, aggressive point guard who went on to play in college. His older brother—a slower, less aggressive shooting guard with seemingly unlimited range—was starring in high school during our formative years and the frequency and intensity with which they played against each other was eye-opening to me.

I played basketball almost every day with friends or teammates, including those two brothers, but I also often went outside by myself and put up shots in the driveway. Thousands upon thousands of shots, all of them unguarded and at my own pace and absent any sort of pressure. Meanwhile in another driveway, my friend and his brother were battling. They contested every shot, scrapped for every point like their lives depended on it, and had a daily intensity to their basketball playing that I experienced maybe once a month.

I bring all of this up partly for catharsis, but also to explain why I’m probably more intrigued than most with professional athlete siblings. I can only imagine life as a great athlete who never really escaped his older brother’s shadow or as a one-time star whose younger brother later surpassed him in the same sport. It all seems so fraught with mixed emotion and motivation and, hopefully in most cases, pride. I also bring all of this up because Kyle Seager is an All-Star third baseman for the Mariners and his little brother, Corey Seager, is an All-Star shortstop for the Dodgers.

Kyle Seager was a college star at North Carolina when Corey Seager was in junior high school. Drafted by the Mariners in the third round, he debuted in 2011 at age 23 and established himself as one of the majors’ best all-around third basemen by combining strong defense with 25-homer power despite calling pitcher-friendly Safeco Field home. Kyle Seager is currently in the midst of what looks like a breakout year, hitting .284/.359/.515 with 22 homers, 31 doubles, and 46 walks in 115 games to rank seventh among all big-league position players in WARP with 5.6.

Corey Seager skipped college when the Dodgers picked him 18th overall in the 2012 draft and gave him $2.35 million to sign. He started his pro career in rookie-ball at the same time his older brother was playing his first full season in the big leagues. Two years later, as Kyle was signing a $100 million contract extension, Corey was being talked about as a consensus top-five prospect. Last year that consensus shifted to Corey being MLB’s consensus no. 1 prospect and he debuted with the Dodgers on September 3 at age 21—two-plus years ahead of his brother’s arrival.

To an only child—or at least this only child—it’s remarkable that a family could produce an athlete as good as Kyle Seager and then produce a second athlete with the potential to fly past his great older brother into a whole different strata of greatness within the same sport. Kyle Seager is one of baseball’s best third basemen. Corey Seager has a chance to be one of the best shortstops of all time. But maybe the truly remarkable thing isn’t that the Seager brothers exist, but rather that baseball history is filled with similar sibling stars.

Attempting to quantify the best baseball siblings can be very tricky. How should you weigh a pair of siblings that includes one inner-circle Hall of Famer and one journeyman—say Hank Aaron and Tommie Aaron or Tony Gwynn and Chris Gwynn—compared to a pair that includes two non-Hall of Fame stars? Sliding that scale too far in one direction puts Babe Ruth and his sister in the mix for best pair of siblings ever, plus focusing too heavily on one sibling sort of defeats the purpose. And what about three or more siblings, like the Molinas or the Alous?

In my subjective, only-child mind the best baseball siblings have to both be star-level players, so let’s focus on brothers who each have multiple All-Star appearances and/or at least 10.0 career WAR, and then sort through that group. At age 28 and 22, respectively, Kyle and Corey Seager have combined for two All-Star games and 28.8 WAR. (I’m using WAR via Baseball-Reference, rather than Baseball Prospectus’ own WARP, because our numbers only go back to 1950 and many of baseball’s best siblings were from the early 1900s.)

Here’s my countdown of the top 10 siblings:

10. The Alomars

Roberto Alomar: 66.8 WAR

Sandy Alomar: 13.7 WAR

Roberto Alomar is a Hall of Famer and one of the 10 best second basemen of all time, making a dozen All-Star teams and winning 10 Gold Glove awards. His older brother Sandy Alomar totaled an unremarkable 13.7 career WAR despite playing 18 seasons in the majors, but through age 31 he was a Rookie of the Year winner and six-time All-Star catcher with a .280/.320/.426 line. Then from age 32 on Sandy hit just .264/.295/.381 while mostly being a part-timer. I’m giving them the small edge over the Molina Brothers Catching Factory, but Yadier might still close the gap.

9. The Bretts

George Brett: 88.4 WAR

Ken Brett: 16.6 WAR

Similar to the Alomars, the Hall of Famer in the Brett family clearly carries this duo. George Brett is one of the five best third basemen of all time. His older brother Ken Brett was, at one time, the more highly touted prospect. Selected fourth overall in the 1966 draft, Ken debuted at age 18 and spent 14 years in the majors as an average-ish starting pitcher. He made one All-Star team and added to his mediocre pitching value by hitting .262/.291/.406 with 10 homers.

8. The Boyers

Ken Boyer: 62.8 WAR

Clete Boyer: 27.6 WAR

Cloyd Boyer: 0.5 WAR

Ken Boyer failed to make the Hall of Fame because his career tailed off after age 33, but given Cooperstown’s scarcity of third basemen he’s a deserving candidate. He won an MVP with the Cardinals in 1963, made seven All-Star teams, won five Gold Gloves, and hit .287/.349/.462 with 282 homers. His younger brother Clete Boyer was also a slick-fielding third baseman and played 16 seasons in the majors, but hit just .242/.299/.372. They had another brother, Cloyd Boyer, who reached the majors before the other two, but lasted just 395 innings as a struggling pitcher.

7. The Alous

Felipe Alou: 42.2 WAR

Matty Alou: 23.2 WAR

Jesus Alou: 0.9 WAR

Felipe, Matty, and Jesus Alou were all outfielders with great contact skills, minimal patience, and high batting averages who played 17, 15, and 15 seasons in the majors. They even shared the same outfield with the Giants in 1963. Felipe had the most power, totaling 206 homers compared to a combined 63 from his brothers. Matty hit .307, so he was an above-average hitter despite the lack of walks and pop. Jesus hit .280, so he managed just 0.9 career WAR while racking up 1,216 hits. Three brothers with decade-plus careers and 1,200-plus hits is a helluva thing.

6. The Ferrells

Wes Ferrell: 61.6 WAR

Rick Ferrell: 29.8 WAR

My first foray into the online baseball world came at what was then called Baseball Primer and seemingly everyone there was constantly arguing about Wes Ferrell’s case for the Hall of Fame. He was a two-time All-Star pitcher who threw 2,600 innings with a 116 ERA+ from 1927-1941, but what made his resume worth bickering about was the fact that he also hit .280/.351/.446 in 1,344 plate appearances. Ferrell totaled 49 WAR as a pitcher and 13 WAR as a hitter. His older brother, Rick Ferrell, actually made the Hall of Fame after an 18-year career as a catcher with a 95 OPS+.

5. The Waners

Paul Waner: 72.8 WAR

Lloyd Waner: 24.1 WAR

Paul and Lloyd Waner are both in the Hall of Fame, but Lloyd was voted in 22 years after retiring and is generally considered one of the worst players in Cooperstown. He was still a really good player, totaling 2,459 hits while being more or less an average hitter for two decades, but Paul is carrying this sibling duo. “Big Poison” won one MVP, was runner-up for another, and racked up 3,152 hits with an .878 OPS that’s 141 points higher than “Little Poison.”

4. The Niekros

Phil Niekro: 96.6 WAR

Joe Niekro: 29.9 WAR

Knuckleballing brothers are fun. Joe Niekro pitched 23 seasons in the majors, logging more than 3,500 innings, and he was the fragile one in the family. His Hall of Fame older brother Phil Niekro was a major leaguer for 24 seasons and threw 5,400 innings to rank fourth all time. Together they won 539 games, faced nearly 38,000 batters, and topped 200 innings in a season 28 times.

3. The Martinezes

Pedro Martinez: 84.0 WAR

Ramon Martinez: 26.3 WAR

Pedro and Ramon Martinez can’t compete with the Niekros’ longevity, but Pedro is Pedro! and Ramon was really good for a decade before injuries ended his career. Ramon Martinez finished runner-up for the Cy Young award as a 22-year-old and threw 1,731 innings with a 3.45 ERA and 26 WAR through age 30. Pedro, who was briefly in the Dodgers’ rotation alongside Ramon, won three Cy Young awards and is the all-time leader in ERA+ among starters. Together they totaled 110 WAR in 4,700 innings, whereas Phil and Joe Niekro totaled 127 WAR in 9,000 innings.

2. The Perrys

Gaylord Perry: 91.0 WAR

Jim Perry: 42.0 WAR

Jim Perry won the Cy Young award in 1970 and then Gaylord Perry won two Cy Young awards in 1972 and 1978. They both had more than 200 career victories—with Gaylord winning 314 games on the way to the Hall of Fame—and combined for eight All-Star appearances and 8,636 innings. Among all siblings, only the Perrys each topped 40 WAR.

1. The DiMaggios

Joe DiMaggio: 78.1 WAR

Dom DiMaggio: 32.0 WAR

Vince DiMaggio: 17.1 WAR

Joe DiMaggio is an inner-circle Hall of Famer and both of his brothers were multi-time All-Stars. As a trio Joe, Dom, and Vince DiMaggio combined for 4,853 hits and 22 All-Star games, which is even more incredible than it looks when you consider they also missed a combined six seasons while serving in the military. Joe and Dom have a reasonable argument for being the best sibling duo ever and once you include Vince to form a trio they stand above the rest.

Thank you for reading

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Sorry, but I keep reading the title of this column as "Banjo Hitler"
Very much enjoyed this, Aaron. I will say, however, that unless your brother is also a sports person, you don't get the "battling" dynamic. I loved playing sports as a kid, but wasn't good enough/dedicated enough to play competitively, but as many times as I tried to con my younger brother into playing with me, he was not interested, and would do so halfheartedly at best. However, even his enthusiastic participation every day would not have turned me into a pro baseball player, so I forgive him.
I always wonder what it's like for the other siblings. Justin Seager was born in between Kyle and Corey, and is toiling away in the M's system, but the odds on him ever making the majors are slim. He's playing pro ball, and living the dream, etc., but he's simply not on the same level as his brothers. That seems like a recipe for some odd, conflicted feelings, but I'm an only child too, so this is yet another situation that I simply can't fathom.