"I disagree with everything my brothers have said in principle," Greg Callahan '05 said with a laugh upon learning that he was the fourth member of the Callahan clan to be interviewed.
Greg and his four younger brothers have all played for their father Bob Callahan '77 on the men's squash team, with three of the siblings playing for Princeton this season. Junior Scott Callahan and freshmen twins Peter and Matt make up the current crop of the family's Tigers, while Greg and Tim '07 form the Callahan alumni section.
Bob Callahan is entering his 27th season as the Tigers' head coach, and for the past eight seasons, he has had at least one of his sons on his team's roster. Living just minutes away from campus, the Callahans have grown up around Princeton squash and have turned the team into a family affair.
"It's something we've all experienced — growing up in tournaments together and playing Princeton squash," said Matt, the youngest brother by 10 minutes. "Not many other things have been consistent through boys one to five."
The Tigers often enjoy dinners at the Callahan home, with players sometimes coming over as friends of the sons, rather than as players on Bob's team. This is just one of the many ways in which squash and family overlap for the Callahans.
"It's impossible to keep them separate," Bob said.
Part of what the Callahans enjoy about Princeton squash is this total immersion experience. The brothers all get along well, and playing together provides yet another realm for family bonding.
"It's like having a best friend around all the time," Scott said.
The Callahans have the unique opportunity to see their brothers both on and off the court, getting to know them on an entirely different level through their shared University experience.
Because family and team life cross so frequently, the Callahans oscillate between calling their father "Dad" and addressing him as "Coach."
"When things are going well, I think of him as the coach," Scott said, "and when things are going bad, I think of him as my dad."
For Tim in particular, there were initially some inhibitions about coming to Princeton and having to balance these two relationships with his father. Helping him through this adjustment process was brother Greg, who already had two years of their father's collegiate coaching under his belt.

"Nine times out of 10, I would try to call him 'Coach' purposely to keep the two [relationships] separate," Greg said.
With multiple sons on his team at once, Bob must be especially careful about treating everyone equally — whether they're ranked first on the team or 20th. To that end, the Callahan boys are coached more often by assistant coach Neil Pomphrey than by their father.
"The best players respect [Coach] for it, and the bottom players love him for it," Scott said. "It makes everyone feel as if they're an integral part of the team."
For Bob, it's tricky to separate the aspects of being both a parent and a coach. He tries to avoid mixing coaching and parenting, helping his sons as much as possible but leaving them room to develop and grow on their own as well.
The Callahans' Tiger teammates see the brothers' unique relationship with their father as a benefit to the team as a whole.
"[They] are some of the hardest-working players on our team," senior captain Tom McKay said.
Not only does playing with the Callahans make Princeton squash a unique experience, but Bob Callahan is also also a unique coach. A four-year squash standout at Princeton, Callahan is one of the most successful coaches in the program's history. He is inspired by the opportunity to work with students and help them make the most of their Princeton experience.
Neither coaching nor squash, however, was originally part of Bob's plan at Princeton. He was originally a tennis recruit, and though he had played squash before, he never really loved it — until he became a Tiger. After his freshman tennis season ended, he was invited to join the squash team by its captain. Hesitant to embrace the sport at first, Callahan was "hooked" on squash after just two weeks of practice.
Callahan still assumed his successful career with Princeton squash would end after his four seasons, but after graduation and a few years working at IBM, he was offered the opportunity to become the Tiger head coach.
After accepting the offer and spending his three-year leave of absence from IBM at Princeton, Callahan faced a decision as to whether or not to return to corporate life.
"I was asked if when I was at IBM in sales I ever had a nervous stomach when thinking about the week ahead," Callahan said. "I was always nervous. At Princeton, I couldn't wait for Monday to arrive and get to work. It made me realize [I wanted to coach], and that's how I made my choice."
Though the descendants of a legendary squash player, most of the Callahan sons do not feel that a bar is set for them, pushing them to succeed. For one of the youngest brothers, though, being a part of Callahan squash tradition hasn't been so pressure-free.
"When you have that last name in the squash community, there are so many expectations to meet the standards," Peter said. "It's been that way my whole life, with expectations to live up to [my dad's] success."
For the most part, though, being a Callahan is about the lighter moments. On Thanksgiving morning, the family plays squash round-robin style, which can get very competitive with so many players — especially because the loser has to wash the dishes.
"It turns out more recently that ... Dad's been the one who's cleaning the dishes," Greg said. "As long as we can beat him, nobody really cares."
Having grown up playing the sport together, the Callahans have come to appreciate the unique opportunity they have to strengthen family ties through squash, while embracing the Princeton team as an extension of their family.
"I wouldn't have it any other way," Bob Callahan said. "They enjoy it, and for me, it's just ... wonderful."