Although the boom of mid-morning thunder rolls across the skies here in South Florida and we woke to thick, humid air, summer is over. The first day of school dawned. And (shudder), I drove my teenager to her first day of high school.

Teenager. High school.

It is a day of wonder, reflection and change marked, appropriately, with a “first day” photograph and an undercurrent of trepidation. For her, the nervousness hit full-force yesterday, as we were shopping for supplies, trying on clothes and buying groceries. The bickering was intense which, more-often-than-not, signifies something unsettled within her. What I marveled at was her ability to bring herself back around to reason quickly.

Me, on the other hand, well… the Immovable Object meets the Irresistible Force. No small surprise, she comes by that iron-will of hers naturally.

Over the past year, my sweet, loving child has oscillated between she-devil and angel. Like stepping gingerly into the surf on a cool day, she’d test the waters, then run headlong back to the safety of the sand to contemplate her next move.

One day, emotions would run high and I’d swear the good Lord had a twisted sense of humor. The next day, the world was bright again, filled with her sweetness and light. I’m sure my own parents have had several good laughs at the karmic irony of DNA.

Watching her yesterday, I knew she had reached another milestone in her development. While we were shopping, she was frustrated, feeling pressed for time and unable to get all of what she wanted right then and there. But instead of dissolving into an endlessly escalating argument, she pulled reason out of her bag of tricks. Whatever conclusions she drew or decisions she made, she made in her head. The back-and-forth, verbal volleyball stopped. And when I turned to her, I noticed the child in her had given way to a spirit more mature.

It was then I realized that all of the tug-of-war, the verbal volleyball, the digging in of her heels, the flexing of her will over the past year were her quickening. These dramatic signs of life were so necessary to her becoming her own person. Summer was over and my little girl had grown.

As I watched her get out of the car this morning and walk toward her classroom, I marveled with pride at the confident, intelligent young woman she has become.