If you’re lucky, despite your lack of merit or any earned grace, you may be fortunate enough a handful of times for a kindred spirit to come alongside you and walk a ways. Over three decades ago, due to the single-handed determination and strong will of her mother, one of those unlikely blessings knitted herself to me at the fragile and tenuous age of fifteen.

Today marks her fiftieth birthday. At the entrance to yet another decade we are lucky to face together,  it strikes me that one of the things that most binds us is that we knew each other when.  Should time clasp its stingy fingers around one of us, which inevitably it someday will, the other will remain to testify to our children. I knew her when.

What a different portrait we can paint than what our children know of us. To them, our moniker is simply “mom,” our presence a given in their universes. Everyone needs a person like this to keep them humble and grounded, to remind them of past innocence and the effort it took to get from there to here. She and I know each other differently, deeply, because we linked arms to weather puberty and periods, chemistry and college, self discovery and the social minefield of high school and beyond. We’d go out on the weekends with friends, me perched on the lid of the toilet while she did her hair and curled her eyelashes. There were braces and boys, angst, acne, and anxieties. Maybe our collective offspring would find it amusing to hear of our exploits, the episodic stories of our coming of age perhaps quaint or provincial to such sophisticated and worldly young adults of 2018. But maybe there’d be a little shock and awe thrown in for good measure at what we each have overcome.

One of my sisters dubbed her “four o’clock Michelle,” because every afternoon after school, our phone would ring and I’d tie up the line for a couple of hours as we downloaded the events of each day. Weekends, we swapped time at each other’s houses, our mothers in the background doing whatever it was mothers did. She taught me how to make excellent snicker doodle cookies, coached me through calculus and chemistry, and exponentially upped my ping pong game in her family’s basement.

Together, we were “not from around here,” having moved in to start high school from out of state–she from Ohio, me from Florida. We shared a lack of southern accents, lots of siblings, and a love of Abba. If that doesn’t say soul sister, I’m not sure what does. We danced to Bananarama and Madonna in the 80’s, were each other’s maids of honor in the 90’s, and compared experiences with marriage and raising children in the 00’s and beyond. I learned to two-step at her wedding when she married that boy from Texas, and, years later, it was her mom I turned to for parenting advice in the absence of my own mother.

Even twenty-five years after my mother’s funeral, she calls or texts on that anniversary to remember and say she’s thinking of me. I follow her parents’ and siblings’ lives, cheer for their successes, and worried over her dad’s recent heart issues. When I saw her standing with her family while we took pictures after my daughter’s wedding, my eyes stung as the emotions welled up. She’s always present for the stuff that matters.

Once, for a month, we were roommates on a college campus. Although we spent almost every moment together in regular life, we didn’t do so well as live-in roomies. Too much of a good thing. But the summer her family camped across the West for a month, I almost died from loneliness. It was before cell phones, and waiting four whole weeks for our reunion was the worst kind of torture. We got used to separation, attending different colleges, for instance, in different states. For years, I visited her in Chicago, Minneapolis, and Texas, while I stayed put with a family business in Tennessee.

For now, she’s only a short drive from here, and we’ve been able to visit more often, each time picking up where we left off, falling into real conversations and the ease and comfort of each other’s company. In construction circles, there’s a thing carpenters use to aid a weak or sagging joint. Apparently, the easiest way to repair a compromised joist is to attach another board of equal or larger size alongside. This board is called–wait for it—a sister board, and the process is known as “sistering.” How brilliant is that? It’s the perfect illustration for life-long friendship, for the person who steps in and holds you up when you’re sagging, who knows just where you need help and just where you’re strong. Who knew you when, knows you now, and loves you anyway. Happy 50th birthday, sister!