Ok. I read through the other answers and am going to give this my two cents, even tough I am the child and not the parent.
This has come up after many years in therapy, mostly classical psychoanalysis.
My mother does not like me because she never got attached to me at birth. A year before my twin sister and I were born, our parents had triplets who all died after a few days. Untreated trauma followed. I was born nearly suffocated and poorly, so my mother, wanting to protect herself from more trauma, never attached to me. She did however to my twin sister who was born healthy and thrived.
Years went by and this initial lack of attached turned into resentment or dislike during my childhood because by the time we were eight years old, our parents were divorced, and I physically resembled my dead-beat father. This only worsened during my teenage years as I was beginning to act up years of neglect and became depressed. She disliked the signs of her own doing neglectful parenting and lack of love in me. I remind her of that.
Ever since we have pretended to get along, but the relationship is never really there. I am a mother of two myself now and have taken all of this on board trying to do better. I am also trying to understand her. That ultimately this was not her fault.