Night Time Woes

My little man Noah has all of the sudden become afraid to go to bed. I cannot think of anything that could have triggered it, but every night at bedtime, he gets really anxious, and asks me every night if he can snuggle with me in my bed instead. We have tried everything from leaving the hall light on, to night lights, to those dream lite pillows, and he is still scared. I am running out of ideas, I am afraid this might just be something he has to outgrow, but it breaks my heart every night. Every night they get songs, stories, and prayers. They have a set routine that has worked for four years until now. Poor Noah, sometimes being little is just hard.