Shari Redstone has a standing invitation to join New England Patriots owner Robert Kraft in his luxury box, where the guest list often includes the likes of Donald Trump, Jon Bon Jovi and Mark Wahlberg.

Instead, the daughter of 92-year-old Sumner Redstone and heir to his media empire prefers her own four seats outside, near the 50-yard line, cheering with less-famous fans even in freezing temperatures.

Redstone, 61, doesn’t hobnob in Hollywood either. She’s never been to the Oscars or the Vanity Fair after-party. Yet she is poised to become the most powerful woman in entertainment, with a big say in what happens at CBS Corp., the most-watched TV network, and Viacom Inc., owner of Paramount Pictures.

Her father, who is in poor health, made Shari and her 29-year-old son, Tyler Korff, the sole family representatives among seven trustees who will control $5.4 billion of stock in CBS and Viacom after he dies. As the eldest family member voting on the trust and mother of three beneficiaries, Redstonewill play a major role at both companies -- even though, under the estate’s structure, she has to share power with other trustees, including Viacom Chief Executive Officer Philippe Dauman.

“Her position is assured to some extent,” said her friend James Packer, the Australian casino billionaire. “Anyone who underestimates her is making a mistake.”

Big questions hang over Sumner Redstone’s empire: Who will succeed him as chairman of Viacom and CBS? Will Viacom recover from shrinking TV ratings? And will either company succumb to merger mania sweeping the media industry?

Friends Speak

Redstone, who divides her time between Boston and New York, declined to comment for this story. She encouraged friends to speak, however. A picture emerges of a leader who prefers to focus on the companies’ success rather than having an operational role; who values being in the family business her father built, and who is keenly interested in the emerging technologies roiling the media industry.

“She’s much more concerned with outcomes than being in the driver’s seat,” said Jon Miller, former CEO of AOL and a partner in Advancit Capital, her Norwood, Massachusetts-based venture capital firm. “She’s been very consistent with me: ‘What I want to see is the companies do well. I don’t have to be an executive in either.’”

Redstone is already a billionaire, having inherited 20 percent of National Amusements Inc., the family theater business where she is president. The company holds the CBS and Viacom stakes.