Vampire Players: What is happening....

My Vampire Sim was sleeping in her coffin when this appeared above it:
https://www.dropbox.com/s/1zkpoieyqqz5onl/02-25-22_12-01-31%C2%A0PM.png?raw=1
What is this and why is it happening? I have never seen this before and very curious as to what it is.
Thanks in advance for any answers.

Your vampire is dreaming.

I should have figured as much but it just seemed so odd. Thanks for letting me know.

Dreaming about a full moon? I wonder if it’s a hint that werewolves are coming...

Wow I play vampires all these years and I never noticed. I thought I knew everything about this game.

I've never noticed this either. Quite strange.

edit: quick note. do you have any mods? I'm going to try to recreate this. I've played vampires since they've come out, the girl in my sig is a vampire (daughter of Straud, actually!) but I've never seen this before.

It might be from a vampire power and/or weakness.

I think there's a weakness that causes vampires to not be able to sleep properly, it may be that

Fitful sleep weakness I believe

My vampire doesn’t have any weaknesses thanks to a mod. I do have a mod that gives my Sims moodlets if they have a bad, good, inspiring… dream. She didn’t have a dream moodlet when she woke up so I don’t think it’s that. In fact she didn't have any new moodlets at all.
She was just sleeping in her coffin. She didn't need to sleep but when I wan't time to go faster I will have her sleep. I have a mod by LittleMsSam that keeps Sims in bed till 6am unless they have a job then it keeps them asleep till it's 2 hours from the time they have to leave for work. Her coffin is also upgraded to have massage control and a better mattress. She also just had a baby in the last 24 hours. I also engraved epitaph on her coffin that day with "Those who enter will be bitten". That's all I can think of that might of caused this to occur.