Haunted nursery

So my babies are sleeping in pitch darkness, and I'm watching them through the baby monitor when I see an orb of light flash by the screen. It freaked me out. Then my baby started stirring.

What's up with this?!

Edit: There's no sulfur smell. But I live on the other side of the world to where my ancestors and recently departed family are from. Could they be here? Or it could be my husband's family. I worry it's a nuisance spirit affecting them since I often have nightmares about being possessed and stalked by demons in the adjoining room.

No jokes, please.