An army of federal agents, bomb-sniffing K-9 dogs, and local police protected Vice President Biden and Republican presidential candidate Donald Trump at Franklin Field on Sunday night while Trump watched his daughter Tiffany and Biden saw his granddaughter Naomi graduate from the University of Pennsylvania's School of Arts & Sciences.

Trump arrived to warm applause from his section but when Biden arrived a few minutes later, the entire stadium erupted in cheering and waving, and he responded by vigorously waving back. Rain and gusty wind briefly threatened to delay the commencement but quickly gave way to a sunny, blue sky.

Tiffany, 22, is the only one of Trump's five children whose mother is the real estate mogul's former wife Marla Maples. Both mother and daughter have said that Maples raised Tiffany as a "single mother" with financial support from Trump.

A few years ago, Tiffany penned and recorded an electro-pop single, "Like a Bird," which includes the lyrics, "You're cute and you're tweeting me; Baby you go 'beep, beep, beep!' "

Tiffany Trump is a prolific poster of posed Instagram photos of herself in a bikini on a tropical beach or on a yacht presumably cruising toward a tropical beach or hanging out with the self-styled "Rich Kids of Instagram."

Her photos have attracted rude, foulmouthed comments, often directed at her famous father, as have her Twitter tweets with more than 20,000 followers.

Naomi Biden, daughter of Joe Biden's son, Hunter, has kept her private life much more private. Naomi spent a week in 2009 volunteering at the Hogar del Niño in the Dominican Republic, caring for young children. On her second day, she wrote in her diary: "One thing I think would make it much easier for all of the nurses working with the babies would be diapers. I know many of the children's families cannot afford normal diapers, but that may be a valuable investment for El Hogar. Especially because so many sheets are dirtied by leaking diapers!"

In August 2011, Naomi accompanied her grandfather on a diplomatic trip to China and set conservative tongues wagging when she disembarked from Air Force Two wearing a miniskirt.

In January this year, she accompanied Biden and his wife, Jill, on a trip to Turkey, during which he criticized the government's crackdown on dissent.

Rachel Jackson from Philadelphia, one of eight family members in attendance to see her nephew Basil Jackson graduate, said: "Tiffany Trump is graduating? Well, so is my nephew Basil. I'm not interested in Tiffany. I'm interested in Basil. He's exciting. Not Trump's daughter."

Blake Tonn's parents, Tracy and Scott Tonn, who flew in from Paradise Valley, Ariz., and his grandparents, Max and Eleanor Schrimsher, who flew in from Scottsdale, Ariz., to watch him graduate, said they were more interested in the crowd reaction to Trump than in seeing the man himself.

Scott Tonn said he hoped the reaction would be polite. "This is about a dad and a grandfather here to see their daughter and granddaughter graduate," he said. "Of course, they come here with a big security posse. But it's still about a dad and a grandfather."

Tracy Tonn said she wasn't surprised by the massive security. "We came here for the Penn Relays a couple of years ago when our daughter competed," she said. "The security was about the same."

Delta Squire from Ocala, Fla., was among 14 family members - parents, grandparents, aunts, cousins, a brother and a sister - to cheer for her niece Amber Hamilton. "For us, Amber is more of a celebrity than Tiffany Trump," she said. "But it's nice that the Trumps and the Bidens are here, enjoying the same thing we are."

Prior to Sunday's graduation, the Daily Pennsylvanian's 34th Street Magazine - an undergraduate-produced, self-described "snarky, inclusive" arts and culture and gossip journal - named Naomi Biden "Most Likely to Have a Penn Building Named After Her" while Tiffany Trump was dubbed "Most Likely to be MVP of the GOP."

The magazine had more fun teasing young Trump, reporting, "Her pre-Penn chart-topper 'Like a Bird' might need a Nashville re-jig but we bank that she'll revv up her mom's Southern drawl . . ."