Ghosts Encounter And Gold Colored Orb

I have a niece named Paula, 23 years old, who is very sickly due to her inborn disease, Hemolytic Anemia, so every week she goes for laboratory tests and check-ups with her doctor.

When Paula was hospitalized last December 2008, she shared to me her horrifying story inside the ICU. From the start of her stay (December 26) there until she came out (December 30), she felt spooky because of some presence around her, as if someone was staring at her and her bed shook from time to time, not violently, but enough movement to feel it. In the night, before she sleeps, her bed is in the proper way but when she wakes up in the morning, her bed and the other equipments that monitor her system are already displaced as if somebody moved it (because all ICU rooms in that wing have individual doors for each patient). Even the nurses that monitor everything were wondering how come her bed goes into different direction in the morning. Paula's Mom never slept there in the night because visitors are not allowed inside; they have specific time to be there as required by the ICU personnel.

Some three days ago, I was seated in the garage when Paula came in (because their house is just beside ours) and entered our main door, I saw a man outside leaning to our gate, very tall, around 6ft in height, thin and was wearing a white T-shirt with small print in the center, but unfortunately, I did not see the face because he vanished at once. I knew that man is definitely a ghost.

After 30 minutes, Paula went home, while I was already inside our house, watching TV. Out of the blue, my attention was caught by a gold colored orb (like the size of a football but round in shape) that came from the main door and disappeared through the middle couch. The distance between the door and the middle couch is around 2-1/2 meters. I usually see orbs but in white color. This is my first time to see a gold orb.

This morning, I just saw somebody again inside the gate but this time, I only saw the edge of the trousers, it was light gray, like my Dad's (he passed away in 1996) and then he disappeared. How strange it is to show up and then go. I re-winded what I saw by repeating how it happened but the entity didn't show up anymore.

Could anyone explain to me (1) the horrifying experience that my niece had inside the ICU room, (2) the ghost that seemed to follow my niece but couldn't enter inside the gate and finally (3) what's the meaning of the gold orb? Is it different from the usual white orbs or is there any special meaning to it? (4) Why do ghosts appear and vanish very fast? Are they correlated to each other? Is there a message that the spirit world wants to disclose?

Thank you for your time in reading my story and hope somebody would be able to enlighten me about my questions.