This happened to my sister about a year ago and that particular night she was really tired and wanted a good nights sleep. My sister's name is Tennikah and like I said, she wanted a good sleep so she locked her bedroom door from the inside so nobody could get in and double checked it was locked and settled down onto her bed.
That night she was awoken by the sound of footsteps walking around her room. Being scared, she just hid under her covers until the sound was gone.
The next morning, there were muddy footprints on her carpet, and we couldn't scrub them off so we had to replace the carpet.
The really weird thing was, that none of my parents has a spare key to her room and we had all gone to bed the time Tennikah heard the footsteps.
My sis was totally freaked out and I had to sleep in her room with her until she recovered. Also, she had many dreams about it too.
Another thing that happened in her room was, one night she heard a ticking noise. Like a clock does, but Tennikah doesn't have or never has had a clock. It was coming from the mantle above her bed. As soon as she looked to where it was coming from, it stopped.
If anyone has any explanations to this story, my sister and I'd really like to know.