Writing just isn't really my thing

I had an idea for a children's story, but right when I try to write it I just loose confidence. All my past books have been crap even though my parents say otherwise. The story idea was simple and something that could get easily published by Simon Pulse romantic comedies, but right when I thought about writing it I just couldn't. *sighs* writing just isn't how it once was. Maybe this is a sign that I'm not supposed to be a fiction writer. Though every time I think of something non-writing job like (modeling, acting) my dad always says,"I think you'll be famous by your writings". Bullcrap! My writing sucks and even though my parents keep saying my writing is good, it's still bad by comparison to other books. Writing just isn't my thing so far and unless I find that confidence I once had in my writings then I don't think I'll be writing any new stories any time soon.