Im back! Story from NOWHERE!

I was walking my dog tonight with my 6 y.o. little girl (who is visiting me for Thanksgiving, thank you very much!) tonight and we got to the dead end on our road. There are woods at the end and she turned to me and said "we can just stop right here...Im not going in those woods!" I asked her why and she just looked at me like I had 4 heads. I laughed and turned around and we came home, but i couldn't get that scene out of my head. I sat down and plotted a story (doesn't involve my little girl) and honestly Im scared just plotting it. I could NOT get that scene out of my head and the plot just flowed as i started writing it down. spent about 2 hours just plotting. I have never had a story just pop out of nowhere like that. Ive always had to really struggle to come up with ideas for stories and they always seemed like I was pushing with them. This one didn't feel that way. This ever happen to you? Do you get ideas from out of the blue? Im going to start on this thing tonight!