'Night-night, God bless - see you in the morning', was always said to me by my mother at bedtime. I also said it to my children and grandchildren when they were young. Like Greatnan commented, it could be anyone's perception of who/what their god is. Also, I wouldn't like to be told that someone was going to pray for me, either.
When my daughter worked nights my granddaughters used to stay overnight with me. They used to love me to read long stories to them, and one night I picked up 'The Bad Fairy Book' (my daughter had bought it for me some time before). On starting the next chapter, I was reading away happily and discovered that what I was reading aloud to my 10 and 11-year-old granddaughters was actually quite explicitly described 'petting' between 'faeries' and wood nymphs! I managed to substitute some of the wording and tell them it was time to settle down to sleep - hence once more, a quick...'Night-night, God bless - see you in the morning!!' 