Is it normal my sister and i had visions of a grandma neither of us knew about?

I am not really sure where this question fits, I guess spirituality and beliefs is the closest.

A lot of tragedy has happened in my family since 2016. Early in the year, my Uncle committed suicide. My sister was very close to him and it devastated her. She had a dream a woman who called herself "Grandma Betty" came to her and comforted her. She decided to ask my Dad (my Uncle was his older brother) about this and it turned out we had a Grandmother named Elizabeth who went by Betty we had never met. I never was told about this.

In October of 2016 I ended up having several seizures in a row and almost died. I couldn't breathe on my own when they found me and I spent time in a coma with a breathing tube down my throat. When I finally came out of the coma, but was not completely aware, I just kept saying, "Grandma Betty is here! She was here!" And similar things.

Again, I had never heard of her, and my sister had never told me of the conversation she had with my Dad about his Grandma. A few weeks later, after I was out of the hospital and more aware, I was told about all the stuff I had been doing under anesthesia (I also thought my boyfriend took back a wedding proposal, lol).

I just think it's interesting the name "Betty" came up for both my sister and me. None of the grandmothers we knew growing up had names similar to that at all, or even close to Elizabeth. If anything, I should have been calling out for a name starting with M, because both my mom's and dad's mom's names start with M. But instead it was Betty.

Betty always seems to be the one there to comfort us. I wish I could have met her when she was alive.