George H.W. Bush was front and center for granddaughter Barbara Bush's wedding to screenwriter Craig Coyne nearly seven weeks before the former president's death

Barbara Bush felt blindsided on April 17 when her namesake grandmother, former First Lady Barbara Bush, died of complications from pulmonary disease at age 92 — more than seven months before her grandfather, former President George H.W. Bush, died at age 94 on Friday.

“We weren’t expecting that,” Barbara, 37, said of her grandmother’s death while speaking to PEOPLE in October.

In April, Barbara was dating Los-Angeles-based screenwriter Craig Coyne, 36 — whom she wed on Oct. 7 — but hadn’t yet introduced him to her grandparents.

“Craig didn’t get to meet my grandmother,” she said. “I thought there would be plenty of time for that to happen.”

Four months later, with an engagement ring on her finger, Barbara decided she wouldn’t make the same mistake with her grandfather.

Credit: Paul Morse

Craig proposed on Aug. 25, during a Bush family gathering at her grandparents’ oceanside home in Kennebunkport, Maine. “We actually would have gotten married the next week if we could have,” said Barbara. “We just thought, let’s try to do it soon. We knew we wanted to be married — we’d already made that decision — so we didn’t need months of an engagement.”

They knew they wanted to wed in Maine, which she called her and Craig’s “happy place” after the couple spent alone time there with her grandfather in early summer, when he returned to Kennebunkport for the first time without his wife.

Craig Coyne (left), George H.W. Bush and Barbara Bush
| Credit: Paul Morse

“It was just us three — quiet and beautiful. I would read to him. While he napped, Craig and I would go on walks, then dress my grandfather up and take him out for martinis and oysters,” she said.

Barbara Bush and Craig Coyne wedding on October 7, 2018. Photo by Paul Morse
Credit: Paul Morse

When, later in the summer, it came to setting a date, the former president’s annual mid-October return to Houston for the winter — along with his age and history of health problems — loomed large.

“He’s great — totally with it. He is, of course, 94 years old and misses my grandmother. … We just thought, let’s try to do [the wedding] soon — a small wedding with just our family and my grandfather, here,” said Barbara, board chair of the Global Health Corps nonprofit she co-founded in 2008.

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At the Sunday evening wedding on his back lawn, Bush beamed in the front row and stayed up to celebrate afterward, an attendee told PEOPLE: “We was there with them all through dinner.”

“That’s the one thing about waiting,” said Barbara. “You can have this great career and this great life. But, of course, the older you get, you lose people that you love.”