The girl who wouldn't ride her bike

At the end of last summer, when Anna was five, she started — tentatively, briefly — to ride her two-wheeler. It was while we were at a campground with a long runway for her to take flight, and she did. There was much fanfare. She was very proud of herself. We were very proud of her.
 
Then it was over. We tried many times after that to get her out on her bike, but she never wanted to. I didn’t worry; I figured that this spring, she’d hop on and be off on those two wheels with wild abandon.
 
That hasn’t happened. We try and try, but we can’t get Anna to go out on her bike. She flatly refuses. Well, maybe twice, Sean has taken her around the block, but she can’t wait to get off. I struggle because I can’t take the girls out bike riding without Anna getting the hang of her two-wheeler (I have a trailer for Avery).
 
Sean is vehemently opposed to putting the training wheels back on, but I think we might need to take that backwards step to help her regain her confidence. If that’s what it is. I’m not sure what’s deterring her. I thought all kids were eager to learn to ride their bikes! “I’m just not interested,” she told me today. I’m at a bit of a loss. 

Anna is a little unpredictable with these kinds of things. For example, she's all over learning to skip right now, and doesn't get frustrated, even when she trips up. But with many new challenges, if it doesn't come easy, she quits (loudly and angrily!).
 
I’ve tried encouraging her day after day, offering to run around the block with her. Then I stopped, because I felt I was nagging her and that was turning her off even more. I told her that once she could ride her bike, she could come on my runs with me, which piqued her interest, but only briefly. I tried leaving on bike rides with Avery (when Sean was home) so Anna would realize the fun she was missing out on. She didn’t care. I even bribed her — telling her I’d buy her whatever she wanted (whatever she wanted!) if she would learn to ride her bike. She was intrigued, but not enough to take the bike out of the backyard. She just likes to talk about what she might ask for.
 
The only bike she will ride is Avery’s little Dora bike with training wheels. She hits her knees on the handlebars and has to peddle her little heart out to get anywhere because it’s so miniature.
 
I really do believe that once she gets going she’ll love it (as I keep telling her) but I’m not sure how to get Anna out there. Should I leave her alone, or keep nudging? What would you do?

Photo by adwriter via Flickr