“Who am I?” philosophers ask. I hate to go all woo-woo, but the question has arisen, what shall I, a new grandma, be called?

Picking a baby’s name is loaded with potential negative feedback. Had my grandson been a daughter, the choice was Mabel (inspired by a barbeque joint near my son and dauther-in-law’s house) Alfreda (merging the names of my husband’s father, Alfred, and my mother, Fraeda.) Bruce Willis may have named his baby Mabel, but I can’t say I love it.  And Alfreda? Really? So I did not want to blow it when christening myself.

The baby’s other grandparents, who live in Germany, picked “Oma” and “Opa”. This left the field wide open. Yet, I had a hard time nailing a name. “Grandmother” struck me as too dignified, and it’s hard to be dignified when you spend half the day in the shorts you wear for your morning run. I considered the classic, “Grandma”, but I’m a creative type and it felt too generic. One sister-in-law goes by “Jamma”, but her first-born grandchild inspired the name, and I didn’t feel I should mooch it, which was the problem with “Gigi” and “Mimi”, friends’ names. My other sister-in-law is “Grammy”, but that was what my own mother had selected; she was diagnosed with Alzheimer’s disease a year later, so in our family, Grammy felt jinxed.

“Nana” is an elegant choice, and what I called my mother’s mother. But I never quite got over how Nana scolded me when at four-years-old, I defiled her sidewalk with a hopscotch grid. I have carried that shame forever. Nana was out.

Last winter, I became devoted to Downton Abbey, with particular appreciation for Dame Maggie Smith, playing Dowager Countess Violet Grantham, the character who asked in all innocence, “What is a weekend?” Her granddaughters called her “Granny”. If that name was good enough for Lady Grantham, it would to be good enough for me, I decided. I gave Granny a trial run with my younger son and his wife, who one day—I hope—will be parents themselves. I wanted them to like whatever name I chose so they would use it, too, because after my parents picked “Grammy” and “Gramps”, when my sister and brother had kids, their children used entirely different names for our Mom and Dad. This has meant that my sons have no shared frame of reference when talking about mutual grandparents with first-cousins. I find this unfortunate.

“I’ll be called ‘Granny’,” I announced.

“Granny?” my son and daughter-in-law repeated, shocked. “Granny is someone ancient and feeble.”

“That’s what I like, the irony,” I explained.

“Yeah, it’s ironic now,” my son responded and asked, “What’s wrong with ‘Nanny’?” the name he calls Helen, my husband’s mom, perennially youthful at 88. “That’s what we call grandmothers in this family.”

So simple. That settled it. I am Nanny Sally.

And you know what? It fits.

Sally Koslow is the author of four novels and the non-fiction book, Slouching Toward Adulthood: Observations from the Not-So-Empty Nest. She became a grandmother in June, 2012.