Should I get legal help?

I live in California and I'm one of only 4 grandchildren. I'm the oldest and spent my hole life at my grandparents house. If you asked anyone who knew my grandparents they'd say I'm the one that helps all the time and never takes from them. While in hospital, my grandpa talked about me taking care of grandma and how much it made my grandpa happy. When nobody came to the hospital it made me upset. My father chewed me out for missing work so I could learn how to help my grandpa get from his wheel chair to his bed. He died and my family changed. Not me. I moved in to my grandparents house to take care of my grandma. I lived there until she got real sick and needed full time care around the clock. I still stayed over night 3 days a week. She always wanted me to sign papers and would say how nobody sees her but if she died they'd only come to see who gets what. I loved her so much and she was like my mother. During her last few years, I fixed up the house here and there with what money I had. I was now married with 2 kids. I moved my family in only after my grandma asked that I stay and how exited she was to be able to see my then baby girl every day. 4 months passed and her dementia took over almost over night. She didn't talk and she locked her self in her room for days. I tried to unlock the door that only made her more upset. My wife was scared and for the kids. I stayed and hoped and prayed she’d snap free like before. Things got bad, I slipped into a depression knowing she had a short time left and my aunt would call and tell me today's the day. Meaning I think she's dying. One day, I walked in even though bed ridden and weak she called out my name, she remembered me. The night before she died I bought her dinner from her favorite restaurant and we talked until 2 am. Later, I was told I was the only one she spoke to and she refused to eat until she saw me walk in. My father took charge of the will. I feel like he and my brother are hiding something from me.