This happened back when I was about 6-years-old, but I was at home sleeping. We were all packed into the upstairs area and I was in the spare bedroom which had no door at the time. Hurricane Opal had just passed through the area and there had been quite a bit of damage to the house so there was this awful aroma throughout almost the entire house. Made it hard to sleep. So while I'm tossing and turning in the night, I hear someone walking around and I sit up to see who it is.
And out of the darkness came this silhouette I didn't recognize and I just felt this aura approaching me. Practically petrified at this point and the figure stops in front of my bed, my nightlight and the blinking alarm clock slightly illuminating them. I vividly remember this moment because they did not appear to be human, but humanoid and they wore this solid brown uniform with small, black tubes on the shoulders, triangular black stripes down the side of their vest and a small black belt. Their face was circular in shape but had these large black diamond eyes that twinkled with lifelessness, and there was also what appeared to be a breathing apparatus resting below their eyes.
They didn't move and I couldn't move. Their head turned down to me and they stoically said "Sleeeeep, chiiiiild," before turning back and disappearing back into the darkness.
I was internally fucking losing it at this point. So I grabbed my stuffed animal and blanket and slipped into the hallway behind them and into my parents room and quietly shut the door, then dove in between mom and dad just quietly freaking out. They woke up and asked what happened and I said someone was in the house. Dad grabs his gun and checks inside and outside the house for awhile and finds nothing. He comes back and says I had a nightmare only to be interrupted by the downstairs door slamming shut. He runs back down there and finds nothing.
Next day we upgraded our home security.