Terri Butler might have missed her high school prom in 1970, but last month she had a chance to go back to the future when her boyfriend surprised her with a belated cotillion of her own.

“I never went to my own prom – life got in the way – so this was really something,” said the Bethel Island resident. “It was a big surprise; not something I expected.”

It turns out missed proms are a bit of a family tradition, so with a the-more-the-merrier attitude, Butler’s sister and daughter-in-law also showed up, plus her son’s fiancé; all of whom had never attended their own high school proms.

“When I found out that Terri had never gone to her prom, I thought, ‘Well, we’ll make our own prom,’” said Spike Donnelly, Butler’s boyfriend. “So the men and I got together and planned a whole prom for the girls. It was a lot of fun.”

The evening started out the obligatory corsages and new dresses (“old age made us smart enough to buy something we could wear again,” said Butler) followed by a Hummer stretch limousine trip to San Francisco, where they hopped onto a Hornblower Yacht for a dinner/dance cruise around the Bay.

An elegant steak dinner and cocktails was followed by music (plenty of l970s hits, of course) and dancing as the ship made its way under the Golden Gate Bridge, around Alcatraz and through McCovey Cove, where a Giants game was in progress.

The group wound up the evening at the Marriott Hotel on Fisherman’s Wharf, where they spent the following day as tourists, traveling to Coit Tower and driving down the world-famous Lombard Street, all the while enjoying the afterglow of a 40-years-in-the-making event.

“It was a great night,” said Donnelly. “The food was great, the weather nice and there were stars in the sky. It was perfect. Better late than never, I say.”

For Butler, late was definitely better. “I can absolutely tell you that I appreciated this now more than I would have then (in high school) – for real,” said Butler. “For one thing, we were legal to drink. But what was really special was that it was a family affair. This was the first time we’ve all had a chance to go out together and do something really special like this. It was really neat.”