Gwen and Terry Zwanziger's 17-year-old daughter Shannon died unexpectedly in 2014 after losing a battle with influenza.

I've cried more times today than I can count. You'd think by now, I could go days without crying, but I can't get over the guilt.

Shannon's only complaint was a sore throat. Her fever wasn't even scary.

Shannon Zwanziger had the flu for a week when she died, her family says.

I spent (wasted is a better word) most of my morning Googling flu information again today. The complex science of mutating viruses leaves me boggled. If I can't make sense of it, how can I explain the importance of stopping the flu to others?

After more than two years, my husband Terry and I haven't said the "D" word yet.

We say "she went to heaven."

We say "she left."

Although I have said, "she died" several times, we somehow can't say the words "Shannon is d..."

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No dreams of Shannon last night. I want to see you again so bad.

If I could just talk to her one last time. Tell her how sorry I am. Does she know? Can she see from heaven? I have mixed feelings about how things work up there, I just know they do.

Going through some books, I came across one of her homemade bookmarks she made, when she was little.

I got a card from the donation center. They're doing a curb pick up next week for "gently used clothing." I can't do it yet.

There are pieces she hardly wore -- her new clothes for senior year -- that she only just began to wear.

So yeah, they're gently used. Just barely used.

Flu Moms

Day 837 is turning out to be an especially bad one. This is the kind of day I should go on Facebook and talk to the other mothers on our private page called "Flu Moms."

Last time I got on, I noticed a couple of new names. Clearly children are still dying.

I thank God for this group of moms.

We can vent and encourage depending on our own mood -- a safe place to share how we feel and how we cope.

Some of the mothers have developed nonprofits to honor their little ones.

They plant municipal flowerbeds and organize 5k runs to raise money for awareness. God bless their efforts.

'Let it run its course'

The seasonal flu kills healthy, active, precious kids every year.

Shannon went to school on a Wednesday, came home like always, but said a friend "gave" her the flu.

I sent her up to her room and began the same things any parent would do.

The flu destroyed Shannon Zwanziger's organs and she didn't even know it, her mother said.

I brought her liquids, applesauce, and soup. She complained of a sore throat, so her dad brought home throat spray, Tylenol, throat lozenges, and a little gift. She developed a fever, but not so high to take her to the ER.

Later that week, I thought she ought to be feeling better, so I wondered if she was taking advantage of days off of school and being waited on.

I'd go into her room and her eyes would be closed. I couldn't tell if she was faking or not. I took her cell phone and tucked it under the clean laundry I'd put on her dresser for her to put away. Next time I went in, she had the phone back, so I knew she was OK.

By Sunday, she just seemed weak.

She was texting and watching TV, but she wasn't eating good and she seemed lethargic. So I sent her to the clinic with her dad, with a little journal of her temperature readings, liquid intake and even her O2 sats.

I didn't go with them because I wanted to clean her room and change her sheets. All nice and fresh for her, you know?

Terry sent me a picture of Shannon sitting in a wheelchair with a mask on, leaning her head on his shoulder.

That's the last picture we have of her.

The last photo Shannon's parents have of her was taken with her father at a clinic waiting for treatment.

When they returned home, she walked in through the back door and said the visit to the doctor was a waste of time.

The doctor just said it was the flu and to "let it run its course."

The doctor didn't have a lot of time to spend with her, because the waiting room was packed with people who seemed to have the flu also. Her high school had something like 150 kids who were out of school with it.

Thirty-four hours later, Shannon came downstairs. When she went into the bathroom, she tapped on the shower curtain, so I helped her into the tub. By this time I was sweating with fear. I hadn't helped her with a bath since she was little.

Something was horribly wrong.

When she leaned back in the tub and I saw her eyes, I knew she was dying.

I got behind her and lifted her out. I sat on the toilet with her sitting on my lap and she died.

There was nothing that could be done to save her.

Health care professionals — from ambulance EMTs to the mighty Mayo Clinic — couldn't bring her back to me.

The flu destroyed her organs. She didn't even know it.

'What if'

Shannon chose not to get vaccinated. I wish she had.

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If I had pushed her into getting a flu shot, then I wouldn't have the guilt about "what if."

What if the vaccine had given her a little extra control over the invasion? That's what the vaccine should do. While you can still get the flu even if you've had a flu shot, it can reduce the risk of serious illness and complications.

Please take the flu seriously.

Keep your loved ones home if you even think they might be sick.

Or else you might live wondering if a classmate died because your child brought that strain into the classroom.

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Talk openly about the flu. Make people around you aware that the flu is deadly.

Talk to every leader you can.

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Companies need to be more understanding about passing the flu around the work place and letting people stay home.

Our government needs to hear from us. They need to be more transparent, honest and forthcoming about the seriousness.

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We need to get our scientists to find a universal flu vaccine. There are research efforts underway working on this.

Instead of guessing in the spring which strains to put into the vaccine, they need a vaccine that will nip it in its core.

Please take action. If we do nothing, then we are all to blame. And believe me, guilt will change your life.

I was just a regular mom of a regular kid.

Now I'm a shell of the person I was.

And the world will never see what Shannon could have become.