I handwrote letters to all 580 of my Facebook friends. I reconnected with old friends and made new ones as a result.

• Amy Weinland Daughters handwrote weekly letters to a Facebook friend she hadn't seen for 30 years.
• It inspired her to write to all 580 of her friends on Facebook.

This as-told-to essay is based on a conversation with Amy Weinland Daughters. It has been edited for length and clarity.

This year, I've handwritten and mailed more than 620 birthday cards to my friends on Facebook — an average of 17 a week.

It costs a lot in terms of stationery, stamps, and effort. But I'm determined that all 980 of them will have received a card by the end of December.

I don't just write, "With love from Amy." I include a long and detailed message. If I run out of space, I'll write on a sheet or two of paper to tuck inside the card.

People often ask why I've made such a huge commitment to keeping in touch with so many individuals.

"Isn't it a lot easier to use social media?" they'll say.

They're right, of course. But I believe that when you send someone a handwritten note or letter, you make a meaningful, priceless connection with a fellow human being.

I wrote a book about my experience writing hundreds and hundreds of letters

The birthday-card project is the follow-up to my successful mission to write personal letters to each of my friends on Facebook. There were 580 of them at the time. It took me nearly two years — between July 2015 and April 2017 — to write them all.

It was the inspiration for my book "Dear Dana: That Time I Went Crazy and Wrote All 580 of my Facebook Friends a Handwritten Letter," which was published last year.

I called it "Dear Dana" because a woman named Dana Rivera was the first person to receive a letter. We worked as counselors at a camp in 1986 but lost touch. She appeared on Facebook as a suggested friend and accepted my request in 2012.

She was a mom of five living in Louisiana. Her youngest child, Parker, had cancer. I did not know these people, but I was immediately drawn to their story. I messaged Dana on Facebook when Parker was having a particularly difficult bout of chemotherapy.

"I'm thinking about you, I'm praying for you. Even though you might not remember who I am," I wrote.

She responded three days later, which amazed me. Who responds to some random person when their son is in treatment?

Later, I was delighted to read that Parker had recovered. Then, after a couple of years, Dana posted that he'd relapsed. That's when I went from minding my own business to not minding my own business.

I hadn't written a letter in 30 years, but the idea was a bolt of lightning. I'm not sure why. Maybe it was inspired by some higher power.

"I'll write to Dana every Sunday," I thought.

It wasn't really logical because I hadn't been part of her life for so long. But I felt so invested that I mailed letters to her and Parker at the Ronald McDonald House near St. Jude Children's Research Hospital in Memphis, Tennessee, where he was being treated.

I continued to write to my Facebook friend Dana after her son died at 15

It almost became like a weekly diary. Instead of "Dear Diary," it was "Dear Dana." I talked about Parker, our memories from camp, and things going on with me. I explained how I'd moved from Texas to Ohio and told her about my family. She didn't write back. I didn't expect her to. Still, it became therapeutic for me. There's something so powerful about looking at your life in a letter, almost from the outside in.

Sadly, Parker died at 15. I have two daughters, and I couldn't begin to imagine the loss of a child. But I refused to stop writing after he died. Dana's husband was an attorney, so I began to send my weekly letters to his office.

Then, four months later — on my 48th birthday — I went out to the mailbox. Nobody sends cards anymore, I thought, but I guess I was hoping for at least something. To my amazement, there was a letter from a person whose handwriting I didn't recognize. Then, I saw the return address in Louisiana. "Oh, my gosh, Dana wrote to me!" I thought. It was one of the greatest moments in my life.

We became pen pals. Dana said that she was able to write things to me that she couldn't share with anyone else. She could fully express her grief to me, while if she spoke with her friends or family, she'd often be afraid of bringing down the room. It became a deep relationship that changed my perspective on a lot of things in life.

"If this can happen with this one random Facebook friend, what else is untapped?" I thought. "What about those other 580 people?"

I wondered what would happen if I wrote to all of them. I put everybody's name on an Excel spreadsheet, printed them out, and cut all the names out. Then I put them in this little box and drew them one at a time. I'd read their Facebook page. Then I'd write them. I'd reintroduce myself, tell them a bit about Dana and my plan to write all these letters, reminisce, and talk about what I'd discovered from their news feed.

I told people I was conducting a 'social experiment'

For example, I might have written, "I didn't know you went to Princeton," or, "I didn't know you competed on 'American Ninja Warrior.'" I was amazed by their accomplishments. "I'm connected to all these people who are badass," I thought.

I'd dive into my memories and figure out how this person fit into my life. I took them out of their Facebook profile and made them real.

I had about 30% of the addresses. The rest I got by asking around. If the person had a workplace, I'd write them there. As a last resort, I'd message them on Facebook. I'd say that I wasn't trying to sell them anything but conducting a social experiment. A few people wanted to check my credentials. But 97% of the time, they gave me their addresses.

I got about a 70% reply rate — mostly handwritten letters and Facebook messages. People seemed overwhelmed that I'd gone to the effort of sitting down with a pen, finding their address, putting a stamp on an envelope, and finding a mailbox. There's something magical about holding something in your hand that someone else has held in their hand. Someone they completely forgot about has shared their handwriting with them.

I've heard "I will save your letter for the rest of my life" over and over again.

I hope others will be inspired by my huge letter-writing project

Dana and I continue to write to each other and talk on the phone. I try to keep in touch with as many people as I can. Over the years, my Facebook friends have almost doubled. It made sense to send them birthday cards this year.

I never dreamed that I'd be an advocate for the lost art of letter writing. But I hope people will be inspired to pick up a pen and write to someone. If each of us shows that we care, we're doing our jobs.

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