The universe is filled with unexplainable mysteries. Here is one of them.

It happened the year after our son Sam passed away from cystic fibrosis at the age of 9. After his memorial, well-meaning folks warned us that the holidays might be especially difficult, so I steeled myself for the big celebrations -- Thanksgiving, Hanukkah, Christmas, and Passover. Our friends were supportive, and we made it through pretty well. I hid behind the crowd of tradition and turkey, songs, and Seders.

But, I was completely blindsided by Mother's Day. This was a different kind of holiday -- intimate, and personal to my husband, John, and me. This was about our family, our children, our private circle of love.

It hurt just thinking about those earlier Mother's Days. The sound of banging pots in the kitchen downstairs, lots of giggling and shushing, heads popping up over the top of the stairwell to our bedroom, three beaming faces holding a tray with breakfast eggs fried sunny-side-up and toast with jelly, handmade cards, a bouquet of flowers from our garden … It was almost unbearable to remember.

You never really believe your child's death is possible, even with all the indications of decline -- not until it actually happens. Maybe not even then. The summer before he turned 9, our family drove north to the mountains for a short vacation, but immediately learned that Sammy's lungs could no longer handle such high elevation with so little oxygen. We had no choice but to return home, all of us stunned and disappointed. In December, his lung collapsed, and a bronchoscopy revealed massive damage. In April, Sam was put on hospice.

By mid-May, it did not look like he would be able to go back to school. He'd already been home for several weeks. Friends visited, and he looked forward to each one, planning to trade baseball cards with a school buddy the Saturday before Mother's Day. But something came up, and his friend never showed. The next day, Mother's Day, Sam slept through the whole day. Two weeks later, he was gone.

In his memory, John planted a special native plant, a Matilija poppy, at our house. Native to two small areas in Southern California, it seemed happy, but -- like many hardy, drought-tolerant plants -- was pretty scrubby-looking for most of the year. That was okay, though. It was one of our favorites. Like Sam, it would have a short but spectacular bloom. Nature, with its cycles and renewals, brought us the comfort we needed so badly.

But then, one year later, I was walking blindly down the long driveway to the mailbox in a sorrowful state, wanting my boy back, knowing that was not to be. At his funeral, people had told me “the love never dies.” True, my love for him had only grown in the year since. But what about his love for me? Was it still somewhere in the Universe? Love that is shared has a circuitry to it, an energy that powers everything, and I was missing his love, feeling the circuitry broken. We would all miss Sam's smiling face tomorrow. All I could think of was how much it would mean to hear his crazy laugh one more time, or get one of his handmade cards.

I stuck my hand in the mailbox and pulled out the mail. There was an envelope with a return address I didn't recognize. I ripped it open as I walked down the long driveway and stood reading it in front of the Matilija poppy.

Inside the envelope was -- no, how could this be? There was a Mother's Day card from Sam.

He had made the card at school the year before, with a homemade rainbow pin, signed “Sam” on the back in his unmistakable handwriting. And wait -- there was a note from his teacher. “Dear Sam,” she wrote. “Here is your rainbow pin! It looks great. The card is the one we made in class. You can add things to it. Hope you're doing well. I miss you. No one can make up puns and corny remarks as quickly as you. With love, Miss M.” I carefully removed the pin from the card and wore it the whole day.

Six months later, I learned that his schoolmate had planned to bring the card with him that day they'd set to trade baseball cards. His mother kept it, and mailed it to me the following year. So, that mystery was explainable.

The unexplainable mystery was the bouquet of flowers Sam sent along with the card. For only then, looking up from reading the letter, did I notice the Matilija poppies had finally burst into glorious bloom, their huge blossoms of pleated white petals looking like eggs fried sunny-side-up, waving in the wind. I laughed out loud to see them. The eggs, the card, the bouquet I wanted? I got them all. And in my laughter, I could hear his. What a gift that was.

That year, and every Mother's Day thereafter, those Matilija poppies bloomed. That's how I know beyond the shadow of a doubt that the love we both shared will never die.

And how and why that is? It's just an unexplainable mystery, truly. This is my “Thank You” note to the Universe.