I was never sure why
My mother started coming into my room late at night, she would pull back my covers and then slide my bottoms down. She would then start sucking on my cock until I came, most of the time there were never any words but sometimes she would tell me because I am such a good kid I deserve this tonight.
I started realizing as I got older that she did it when she drank to much but I was never sure why this was what came to her mind to do. I always let her do it not wanting to upset her and I could not deny that it felt very good. She even fell asleep right on my bed sometimes after finishing, I would slide myself over to give her more room or go sleep on the couch. It was just the two of us so sleeping anywhere in the house was never a problem.
I realize now as an adult that she was a heavy drinker and I am sure most nights she had no memory of doing it and alcohol was primary reason she did it.