The author, at right, with her mother in San Diego last year. (Photo by Todd London)

Karen Hartman is a playwright and lecturer at Yale University.

My mother gave me the locket for no occasion at all. “I was going to put in a picture of my grandmother and a picture of my mother, but I guess I never did,” she said as she extended the gold deco disk on a flimsy chain.

“Maybe I’ll put in a picture of Grandma and a picture of you,” I answered.

Mom looked stricken. When my grandmother was pregnant with her in 1943, their bodies rejected one another because of mismatched blood. Mom was born 10 weeks premature, barely over four pounds, the only live birth of Grandma’s three pregnancies. My newborn mother lay untouched in an incubator for her first eight weeks until she was strong enough to come home. Now her face froze, as if shutting her up too closely with Grandma might kill one of them still.

I recognized that look. Our blood matches fine, but I wouldn’t want to be locked face-to-face with my mom, either. In our family, mothers and daughters love from a distance.

I knew Grandma as an undiscriminating lady in hand-sewn polyester pants. She ate scraps off plates. She once downed a full glass of my brother’s orange juice standing up at a restaurant, coat on, purse clutched, so it wouldn’t get dumped. Grandma refilled glass jars from the Sparkletts water company and set them in the refrigerator, where algae grew in their mouths. Her eyes were bad; her health was good. When we drove the 90 miles from San Diego to Anaheim to pick up Grandma for the weekend, my little brother Aaron and I would watch Mom attack her kitchen with bleach.

Mom made me peer into the water jar clouded with soft, green strands. “Grandma drinks from this,” she said. “It’s sad.”

Yet Grandma smiled constantly, walked miles every day until she was 80 and wore holes in the soles of her drugstore-brand Keds.

Mom grew up picking through moldy food, burst cans and spices as old as she was that moved west with Grandma in the 1970s. While Mom scrapped jars and tossed out foil-wrapped leftovers in the kitchen of Grandma’s one-bedroom apartment, her mother would heckle from the sofa. “Don’t throw that out! Why are you throwing it out?” she’d squawk. Then Aaron, Grandma and I would hang out by the pool in her senior complex while Mom wrecked her hands with a new can of Comet.

I don’t know what creates a bond. I was born without incident, but somehow Mom got abandoned in the recovery room and couldn’t hold me for half a day.

Mom jokes about my first steps, saying that kids are supposed to walk toward their mothers, but I walked away. She promoted my independence, transferring milk into a small pitcher so I could pour it myself and keeping stepstools in each room so I wouldn’t have to ask for help. I went east for college at 17, sometimes letting a year or more elapse between brief visits. I didn’t drop my mother, but I didn’t always return her calls.

Mom bought Grandma a small condo in San Diego, where she stayed for nine years until the weekend my brother graduated college, when Grandma fell, losing the last of her eyesight and her sense of direction. Mom, who had just moved after a tough second marriage, took in her blind, 87-year-old mother and tended to her alone for more than a year. Then she visited nursing homes the way she once chose schools for us, grilling the staff about how many times a week residents were bathed and whether there were gates on the stairways. Unsatisfied, she hired someone to watch Grandma in her condo, three blocks from Mom’s new place, while Mom shopped and cooked.

Once when I picked up Grandma and drove her those three blocks, she cawed, “Why was it so short?” Mom went in circles, I learned, so Grandma wouldn’t know she lived so close.

Grandma never got sick. “Homemade penicillin,” Mom said of the mold. Then, at 95, she gradually lost the ability to move, became bedridden and started to suffer. On the advice of hospice, my mom brought her to an inpatient facility, where she lasted just nine days. Mom paid a young woman to hold Grandma’s hand, so that she would have constant human touch. Mom sat by her side. She slept over. She asked Grandma’s preference about her pillow’s position, swabbed liquid on her lips. Grandma mouthed words we couldn’t hear. “Water?” Mom repeated. “Too hot?”

I’m pretty sure it was “I love you,” every time.

While Grandma was living with her, Mom called me with a long-term-care policy packet in front of her. “It costs $150 a month,” she said. “Will you promise to pay the $150 if I can’t? So you won’t have to change my diaper? If I miss one month, I lose the policy. Will you promise?”

“I don’t have money. I’ll never have money.” What I had was debt. “If it makes you feel better, sure,” I said. I wished even then that I’d been more generous.

We buried Grandma next to my grandfather Max on a spring day in 2004 in Chicago, where no one in my family has lived since 1946. My mother was surprised I came to the funeral. She had planned to bury her mother alone.

When my son was born six years ago, my mother and I started spending long weeks under each other’s roofs. She is his only biological grandparent, and a spectacular one at that, so we made it work. But whenever Mom walked into a room, I would start wondering how to walk out.

Last spring Mom was diagnosed with multiple myeloma, a blood cancer. She waited a month to tell my brother and me because his first child was born the day of the diagnosis and she didn’t want to wreck the joy.

Rather than canceling a trip to New York to see the baby and cover work travel for me and my husband, she stayed a week, carted our son to and from preschool, cleaned, cooked and visited her new granddaughter. The only clue that something was off was that she took taxis. Frugal and vigorous, my mother usually walked or took the bus.

The day after Mother’s Day, Mom called to schedule time for a talk with Aaron and me. Mom doesn’t schedule, so I said, “How about now?” and got Aaron on the phone. Mom explained that the first symptom had been sharp pain in her ribs and that there is treatment but no cure.

“You kids shouldn’t have to deal with this,” is where she wept, “after all you went through with your dad.” Our father died from a liposarcoma 10 years earlier, surrounded by family.

I put on the empty locket, an amulet to protect not me but her.

The next day I looked up former colleagues of my hematologist/oncologist father to see if anyone could recommend the best doctor in San Diego for my mom’s condition. I booked a flight. Mom seemed shocked to see me. We went together to her doctors.

She noticed the locket. “I worry about that chain,” is all she said.

This past year my mother has endured bone pain, a blood clot, neuropathy, night sweats, disorientation and intense fatigue. When she entered the hospital for a stem-cell transplant, she left me a refrigerator full of food and a thicker chain. I visited five times over seven months, bringing family when I could. I correspond with doctors and track her appointments in an iCal calendar labeled “Mom.” For a while I called every day.

At one point my mother said on the phone, “Thank you for taking an interest.” As if I were a neighbor with a pie.

“You’re my mother,” I said. “If I were sick, wouldn’t you take an interest?”

She couldn’t see it as a parallel situation.

I keep waiting for the illness to bring us closer, to melt differences, to give us more to share besides the hard part. But maybe this is it. Maybe intimacy is distinct from love.

I hope Mom will once again survive her traitorous blood. I hope she is at the forefront of curable multiple myeloma. At any rate, she feels better now and is expected to have a long road.

Which gives me years, I hope, to learn how to say what your mother’s picture in a locket is supposed to mean: You are not alone.

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