Eight minutes past 5 a.m. and the sodden morning air already smells of the day’s promise. The dog is tugging at her leash when, from my doorstep, I spot balloons waving gaily from the mailbox.

They’re accompanied by a sweet note from a yet-unnamed admirer —and a sonogram photograph that in the dark makes this darling, this newest thief of my heart, resemble a tadpole instead of the cherubic-faced child I’m sure it will become.

I’m to be a grandmother again. Grandchild No. 5.

My family is multiplying, a happy event, and at times it seems that I’m responsible, in one way or another, for much of the population growth of a nearby ZIP code. The next generation has been busy; a fresh baby crop will be out this fall. My niece is due in September, my nephew’s wife in October and my daughter-in-law a month later.

Felicidades and mazel tov. A prayer of gratitude is forthcoming.

Two days after this unexpected announcement, the country of my grandchildren’s births marked a milestone of its own. The Census Bureau announced that, after years of projections, non-Hispanic whites no longer account for the majority of U.S. births. In the 12-month period that ended last July, births of minorities — Hispanics, blacks, Asians and people of mixed race — reached a majority for the first time.

My family’s next generation is part of a tectonic shift, with broad implications for our society. William H. Frey, senior demographer at the Brookings Institution, told the New York Times we are witnessing a “transformation from a mostly white baby boomer culture to the more globalized multiethnic country.”

Tomorrow’s generation will be more diverse and less easy to define or divide along the traditional black-white line.

Because I live in Miami, where this has long been the case, I initially shrugged off the new numbers. The Census Bureau announcement felt like the rest of the country finally catching up to us.

But this doesn’t sit well with some folks — change never does — and the Internet has buzzed with doomsday predictions about the demise of “American values.”

My celebration apparently is an affront to others. As if descendants of North Europeans had a lock on commitment to family, country, hard work and sacrifice. As if the traditions of the past provided the only map to success. As if certain immigrants from certain countries, with certain physical characteristics, were the only ones worth welcoming.

How sad, and insulting, to read such stupidity. How very short-sighted.

Tomorrow’s generation already lives among us. It’s as American as apple pie a la mode, sauerkraut on hotdogs or chips with salsa. Tomorrow’s generation is your heart surgeon and your gardener, the legal secretary and the Wal-Mart cashier, your grandson’s best friend and your favorite newspaper columnist. It is sometimes tow-headed and sometimes almond-eyed, sallow-faced and brown-skinned, tall and short, thin and barrel-chested, Catholic, Protestant, Baptist, Buddhist and Muslim.

Tomorrow’s generation may not be heralded by silver balloons tied to a mailbox, as mine was, but I see it represented in my grandchildren, the blond and the dark-haired, the Irish-Cuban and the Honduran-Chilean by way of Alabama. I see it and, once again, I’m filled with hope and optimism for what’s to come.

Americans, one and all, and dang proud of it.

Follow Ana on Twitter @AnaVeciana.