When I was about 12 or so I had a blue furry nightlight in my room. It was the middle of the night and I was asleep and then woke up and saw the silhouette of my mom in her pajamas she always wore. I said "mom?" wondering what she would be doing in my room randomly and I heard a startled "huh" noise and she ducked down in front of my bed so I couldn't see her. So I got out of bed and looked under and around the bed and no one was there. I still wasn't freaked about because my mom is so sweet and would often secretly leave little surprises for me and my other siblings. So I was thinking ok whatever I'll ask her what she was up to in the morning.
I wake up the next day and approached my mom to ask why she was being sneaky in my room last night and she was just like what are you talking about. I interrogated her for about 10 minutes telling her I saw her and if she was hiding a present for me or something and she finally said "I promise I was not in your room last night." I was so freaked out then because I saw her and heard her get startled when (whatever it was) saw me, and then nothing was there!
A few years later, I must have been 16 or so, I had rearranged my room and my mom no longer had that pajama set. I still had a night light, but it wasn't a big flamboyant furry blue one, just a small dim light. I woke up again in the middle of the night and saw her silhouette again, with those same pajamas, and this time knew it wasn't my mom and I just got so scared and hid under the covers, because we all know that anything ghostly thing could never possibly get you under there... Lol.... But really thinking about the silhouette of my non-mom still gives me chills....