A shadow person?

When I was in elementary school, I shared a queen size bed with my older sister and our family dog (a mutt that looked like a short haired Lassie) would sleep at the foot of our bed every night. When I was about 6 years old, I woke up one night around midnight and saw a dark figure standing at the foot of the bed. The figure was entirely in black without any eyes or a face. I tried to wake my sister up, but she rolled over to go back to sleep. My sister must have accidentally kicked the dog, because the dog woke up and raised her head and started growling at the figure at the foot of the bed. The growling then woke my sister up and she saw the figure and started screaming. When my parents came into the room and turned the light on, nothing was there.