Acknowledge the fear. While a fear of the dark may seem irrational to you, it’s very real to your toddler — so ignoring it won’t make it go away. …
Stay in bed and keep the lights off (don’t switch suddenly the light on and better to comfort in bed in own room)
Play in the dark. …
Try relaxation training. …
Offer a security object. …
Leave a little light on. …
Check on her. …
Work with her imagination.
And yes, monster spray 🙂

A night light definitely helps soothe their fears, they can see what’s there and what’s not with one of these.

We gave our eldest a nightlight and a special toy to take to bed. We used to look everywhere in her room and the house to make sure there were no monsters in the house. Then we would tell her that monsters didn’t come into houses with mummies and daddies because they were scared of us! Worked for her.

lol i went through this with my daughter and probably because of monster’s inc lol. It is funny that such an innocent movie still sparked fears lol. we solved this by going into her room and pretending to do karate moves on the invisible monster and declaring that we kicked it’s butt! our daughter asked us to come in and kick the monster’s butt lol. Only had to play this game for a week before she got over it. We tried to turn the situation into a positive and funny one.

Maybe put a small bunch of flower in the room or a pot of mint etc and tell her that monsters will not come into her room while thats there.
I do have to admit i had a bad dream after watching monster inc once although i did wake up after the fright laughing how silly i was. Maybe it something in the back of her mind she need to let go of.

I have also heard about the spray being very effective. If you use water and lavender it should help her sleep too

I was going to propose exactly what BEC101 said. I read this article time ago http://www.huffingtonpost.com.au/2014/03/12/pharmacy-prescribed-monster-spray_n_4944297.html?ir=Australia and I found it really interesting. You can make your own bottle, fill it with water and essential oil, decorate it, and give it to the child. Or spray it yourself in the evening.

I saw on Facebook a post last week a bottle of spray that’s “monster spray”. You could spray that before she goes to sleep (maybe water and lavender)
I’m just not sure whether that comes across as monsters are real.. Let’s get rid of them this way..
Each kid is different I guess

Try buying an aerosol and writing monster spray on it. Spray it around her room in front of her and tell her it will keep all the bad monsters away. Any airfreshener will do. In the am, just ask her why she thinks there are monsters out to get her. She may be calmer during the day about it.