She may get answers now that the District Attorney's Office - which hadn't given the case much thought until we put Christina's photo on the cover of the Daily News - has convened a grand jury to investigate it (thank you for that, Deputy D.A. Ed McCann). Sankey is waiting, too, for the Philadelphia medical examiner to decree the cause of her daughter's death, although it appears she froze in the bitter morning air.
The waiting is torture.
When she lost Christina, the world caved in on Sankey and her younger daughter, Liza, who is also intellectually disabled. They'd been the Three Musketeers, life having whittled away the others for whom Sankey had cared over the decades: Her needy former husband. Her ill mother and autistic brother - both now deceased.
Over the past few years, Sankey had relaxed into the rhythm of caring for her daughters and haggling with the state for services she couldn't afford to provide them. She is terribly poor - indeed, she doesn't even own a bed. She sleeps upright in a wooden rocker; Liza curls into a sagging love seat. And the bills are harder to pay now that Sankey has lost the Social Security benefit that Christina used to receive.
But, she says, "We never needed a lot. We had each other."
Now that it's just her and Liza, she says, the days are too long, the nights longer as she mourns the loss of the daughter whose bear hugs left her breathless.
"I wasn't finished taking care of her," she says.
She is obsessed with learning what happened in Christina's final hours. So when I tell her that I'm heading to West Philly to check out a reader's tip about Christina, Sankey comes along.
We park at 54th Street and Lansdowne Avenue and walk west, because this is where the reader, who contacted me at work, swears she used to see Christina wander, long before she went missing.
We show Christina's photo to those we meet in the Lansdowne Food Market, Bob Turner's Hair Gallery, the Lucky Garden, ToPhades Barber Shop, Rite-Aid, Dexter Laundromat.
It's a bust. No one has ever seen Christina, but the kindness they show Sankey comforts her.
"People care," she says.
We then head to the address where Christina's body was found. Sankey has never been here, and she sways in grief as she stares at the spot where a passer-by discovered Christina lying between the cars, her head on the curb, two trash-can lids atop her naked torso.
"I'm so sorry," I say, rubbing her shoulder. She moves away.
"I don't want people to see me cry," she says. "I need a minute."
She sips a bottle of water as we drive to the Southwest Philly neighborhood where Christina's former caretaker lives. Sankey just wants to see where Hussanatu "Ayesha" Wulu spends her days now that she has been fired from Casmir Care Services, the agency that employed Wulu until Christina's death.
"Ayesha knows where I live. She knew everything about my Christina," says Sankey. "I think I deserve to see where she lives."
We park. Sankey takes in Wulu's house, the quiet block, the undertaker's office on one corner, the school on another. She hasn't the energy or inclination to climb out of the car, let alone to knock on Wulu's door. So we pull away and head to ShopRite to buy her weekly groceries - a trip she usually makes by unlicensed cab, because she has no car, and public transit is painful on her bad back and diabetic feet.
Normally, the trip costs $25. The money she saves today can be used to buy extra hamburger.
Lord, it takes a lot of money to be poor.
Groceries packed, we head back to Point Breeze, where Sankey will spend another fitful night in her rocker, the latest in a lifetime of such nights, now that one Musketeer is gone.
"I worry that everyone will forget my Christina," she says. She hopes I will write a column reminding readers that she loved her daughter as much as any mother would love a "normal" child. And that Christina was a loving person who was happy, despite the disabilities that might make others assume otherwise.
"Please write that," she says.
On Twitter: @RonniePhilly