By Tim McNicholas

CHICAGO (CBS) — Nearly 3,000 people died on Sept. 11, 2001– 3,000 lives cut short and 3,000 families missing a loved one.

CBS 2 Morning Insider Tim McNicholas shares the story of a widow in the Chicago suburbs making sure her husband’s legacy lives on.

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Twenty years later, Sue Mladenik’s trips to memorials aren’t getting any easier.

“It’s kind of gut wrenching,” she said. “He was just, there wasn’t anything that he wouldn’t do for somebody else.”

Her husband, Jeff, a beloved pastor at Christ Church of Oak Brook, had been traveling for work on Sept. 11, 2001. He was scheduled to fly from Boston to Los Angeles.

As Sue watched the news unfold back home in Hinsdale, she started to worry.

“I tried calling Jeff all day. I kept leaving him voicemails. He never called me back,” she said.

So she called his office to try to ask what flight he was on. Flight 11, they told her, American Airlines.

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“American would not tell me whether or not he was actually on that flight,” she said. “And I just said I’m not hanging up until somebody tells me whether my husband was on that plane or not. And they said, ‘Hold on. We need to get a crisis counselor. So that’s when I knew.”

Jeff and Sue had four kids together when he died, including three biological children and little Grace from China, who they had adopted in 1998. The couple was in the process of adopting another child from China, who they’d already named Hannah.

“He was pretty excited,” Sue said.

She went ahead with the adoption and raised Hannah on her own.

Then in 2004, she adopted Bethany — also from China.

The youngest Mladenik children may lack memories of their father, but just like the rest of the family, they fight through heartache every Sept. 11.

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“I feel like all my kids, and now my grandkids, are Jeff’s greatest legacy. They carry on his name. We talk about him all the time. We don’t want people to forget. He mattered.”

Tim McNicholas