Do I have a "leg to stand on" in regards to my deceased father's property?

My father recently passed away without revising his will from 1984 (leaving me a dollar and my sister the house).

Over the past 14 years I have spent about 10 years in my father's home taking care of him; the last part being nearly 3 years straight. Last year my sister, my father and I discussed having the house in my name and upon the death of my father and if I sold the house, the remaining profit would be split between my sister and I. She agreed to this and signed an agreement. I then drew up a quitclaim deed that was signed by my father and notarized.

Very shortly thereafter a toxin release from a non-functioning liver began taking its toll on my father's mental capacity so I did not go the one step further by filing with the court this quitclaim deed due to him not being able to sign the tax documents and claim he was in his right mind.

My father passed away early this January. In the past 2 weeks, my sister has decided to conveniently forget all this including the massive amount of my life spent taking care of him (got the city to step in and make necessary repairs to his house, was medical power of attorney and ensured his health was heavily monitored as well as his prescriptions, among dozens of daily things taking care of him). I'm now in the horrible position of being a single mom in a home that can be ripped out from underneath me.

Will a judge take one look at the 10 years of documented care, the quitclaim deed, the signed agreement, as well as many other pieces of paperwork and neighbors who would easily attest to my attention over the past decade and just simply go by the letter of the will?

Thank you for your time and I hope I have clarified my question sufficiently.

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