I Can See Spirits

I am just going to hop right into this story. I recently have had some really weird things happen. I can see spirits. Or I think anyway. I see them for a split second, but as soon as I blink they are gone. However, it's like mentally I can see what they are doing, what they look like, I can mentally hear anything they say. Is this possible? If I see a ghost Physically for a split second, I can then mentally tell you what they look like, if they are saying or doing anything also. But, here lately, some weird things have been happening. I just got a pool, and I swim in it a lot, I feel very relaxed and calm in it, and it seems that I see a lot of spirits while I am in the pool. Why is this? One spirit I saw, addressed himself as my step-father's grandfather, he just stopped in to see his grandson, I knew he was a farmer from his clothing and his straw hat, he had the same squinty eyes as my step-father's mother does. After this spirit finished talking to me, I mentally seen him in the field, calling to a cow. The cow, walked up to him and stopped exactly where I saw the spirit and acted as if someone was petting it. I later asked my step-dad if his grandpa was a farmer and he answered yes. But, I didn't tell him why. I also seen a little girl dressed in a white dress that look like a wedding dress. I was in my pool, and I seen her veil running over the rail, and then I seen her full body in mental images, She told me she was a flower girl for her mother, when her mother re-married. And she was dressed like a Mini-Bride. I believe she may have passed away due to breathing problems, maybe asthma? I am not really sure. Last night, while in my brother's room, I heard a little girl PHYSICALLY (this is a new one for me, I have never heard a ghost speak so clearly physically), She clearly yelled, "hey" as if she wanted to get my attention. I thought I was the only one in my family who could see spirits. But my mother recently told me that she had seen them since she was little. My little sister had her first encounter with a spirit the other night. She was alone and said a man walked in her room and look very angry. But stood there for a few seconds and left calmly. My question is 1.) why do I see more spirits when I am in my pool? And 2.) Why can I only see a spirit physically for a few seconds and then see and hear everything else in mental images?