Hey! So this is an idea I've been playing around with for a while. It's slightly AU-ish, as I've already worked out a plot up which sticks to the storyline up to episode 14.

Hope you enjoy!

"I'm sorry... Momma please... I'm sorry..." Regina cowered in the corner, her tiny frame shaking with tears of pure fear.
Towering over her daughter, Cora was a picture of fury, "How dare you disobey me!"
"I'm.. I'm sorry..." Her crime? The six year old had walked into her mother's study while the older woman had been weaving a spell. Her lip already carried the mark of Cora's first magical blow.
Having run to her room, Regina was no more than a quivering wreck. Cora's hand rose to throw another spell, as Regina flinched, a ball of fur teeth and claws launched seemingly from nowhere and wrapped itself around the older woman's hand.
With a cry, Cora lost control of the spell; blasting herself and the cat across the room. Moving faster than the woman, the cat leapt back at her; claws slashing wildly.
Regina had stumbled to her feet, "Smokey, no!"
Cora managed to hit the cat, knocking it out onto the balcony. Jumping to her feet, Cora launched a powerful ball of magic at the feline; sending it hurtling over the edge and out of sight.
"Smokey!" Breaking down into uncontrollable sobs, Regina sank to the floor.
Straightening her dress, Cora snarled, "Stop that crying! Or I'll send you after her."
Swallowing her sobs, Regina nodded, "Yes momma."

Waking suddenly, Regina frowned. Since her mother's return her memories of abuse had plagued her. But this particular memory confused her. It had been decades since she had given a thought to the incident. Running a hand through her hair she chalked it up to restless sleep. Sighing, she sank back into the pillows, and allowed herself to drift back into a dreamless sleep.

The next morning, when the door to Granny's opened, Ruby turned to see a face she didn't recognise. "Hello, welcome to Storybrooke." An unsettling feeling began to wash over her.
Seeing wolf frowning, the stranger wore a slight grin, "Relax, I'm a resident."
"Oh! How come I haven't seen you around?"
The woman had an unusually smooth voice. Her words flowed easily, her smile and brilliant green eyes reassured Red completely, "It would seem my Storybrooke counterpart was much like my true self in, in that I very much keep myself to myself." Extending her hand, her smile widened, "Call me Chess."
"I'm Red, nice to meet you." Releasing the woman's unusually soft hand, she asked, "What can I get you?"
"Tea, if you please."

As Regina followed her mother through the woods to the spot where Rumplestiltskin's dagger was buried, she found her mind wandering. Damn it Emma. Why did you have to chose now to leave town? It was true she was no fan of the dark one, but she was concerned about what other plans her mother held for the residents of Storybrooke once they had control of Stiltskin. As much as she desperately wanted to believe her mother had changed, she just couldn't risk Henrys safety by taking her word. Not that her mother's offer hadn't enticed her; it had. But for something inside of her was rallied against the violent plan; even if it was to get Henry back. Cora had been a brutal mother, she had hurt and killed in order to keep Regina in line, and under her control. Her hands curled into fists, as she felt magic crackle in her palms. Gritting her teeth against the surge of childhood memories, Regina again swore never to do that to her own son. "How much further?"
Looking over the map, Cora took three more steps before stopping, "Here."

As she dug, Regina paused. Sitting about twenty meters away from them was a bluey grey cat. Straightening, she pretended her back was stiff. Cora reached out for the shovel, eager to reach the dagger, "Let me."
Nodding, she allowed her mother to keep digging. Stepping up out of the hole, she studied the cat. Tilting her head, she paused when she realised the feline mirrored her gesture. There was something strange about it, that she almost recognised. Assuming it was one of the many strays brought along for the ride with the curse, she disregarded it. Her heart stopped dead when she heard a hollow thunk behind her.
"This is it!" Cora panted. Throwing the shovel aside, she uncovered the rest of the box by hand, "Here, help me."
Reaching in, Regina took hold of one handle; pulling it out of the ground. Stumbling slightly, she dropped it on the side of the hole. Regaining her balance, she cast her eyes around to where the cat had been sitting; the animal was nowhere in sight.

I realise I haven't given you much to go on here, but what do you think so far?