“They told me to have two! They said they’d play together,” my mother yelled.

My sister and I were so startled by her impassioned proclamation that we stopped squabbling over whose turn it was to feed the turtle.

The competition between us started early.

When my mom came home from the hospital, she bent down to show the new baby to my sister. A little hand dangled from the bundle of joy—and Rosemary couldn’t resist taking a bite.

Today I love the verse from Ecclesiastes: “Two are better than one, because they have a good return for their labor: If either of them falls down, one can help the other up.”

But, frankly, as a child it made no sense to me.

You see, war between my sister and me could develop over something as simple as sharing a slice of cake.

The rule was etched in stone in our minds—one sister wielded the knife, sinking its shiny edge into the succulent chocolate flesh, and the other one chose which slice she wanted.

The size differential was often so slim you needed a microscope to determine which piece was larger.

But in our world, the cake war was significant—and whenever one sister dared break the rule, things got ugly.

Fortunately, there were times we declared truces, such as the day we joined forces against a common threat.

Our mother went back to teaching when I was two years old and my sister was four. This meant that each morning, a stout, stern person known as the babysitter entered our lives—and tried to assume our mother’s role.

This attempt was doomed from the get-go, since my sister and I worshipped our beautiful mother.

After all, she cuddled us, fed us and chased away imaginary beasts from under the bed. She could sing, sew, cook, knit—and draw crayon faces on the shells of soft-boiled eggs.

Our first attempt at scaring off the babysitter was screaming bloody murder as our mother left the house.

Years later, our mom reported hearing our piteous cries at the bus stop a block away—and suffering greatly when people around her commented, “Those poor babies! What’s the matter with mothers today?”

When screaming didn’t work, Rosemary devised a rather elegant plan to bring our mother back home, which entailed upending a tall set of bookshelves. In our little minds, this would so rattle the babysitter that she would quit.

My role was simple enough—stand clear and keep my mouth shut.

The bookcase went crashing over, the babysitter yelled at us and banished us to our room. She cleaned up the books, went back to watching TV—and returned the next day.

All these years later, I agree with Ecclesiastes about two being better than one, for a variety of reasons.

First, if my mother had stopped at one child, I would never have existed—and you wouldn’t be reading this column.

Also, life would be quite lonely without my sister, who earned my undying respect when she became the mother of three children.

Sometimes, when I’d visit her, the Great Dane would be running through the house entangled in the phone cord and the couch would be sprinkled with Fruit Loops.

The kids were crying because someone had eaten the last cookie, and the hamster had escaped from his cage.

I was single and living a quiet, orderly life, so I would often sequester myself in the guest room to escape the mayhem.

Meanwhile, my sister calmly changed diapers, refereed battles among the kids and located the hamster, who’d taken up refuge in someone’s shoe.

And just like it says in Ecclesiastes, we’ve helped each other up over the years.

When her husband died, I went to the funeral and held her hand during the service. When the same tragedy happened to me, she returned the favor.

We can now reminsice about the days when we threw tantrums about turtles and battled babysitters, and have a good chuckle.

Still, when it comes to sharing a piece of cake, we follow the traditional rule: “If you slice it, you don’t choose it.”

After all these years, it still keeps the peace.