Lmao, a "fat girl's" bike? Wouldn't that be one of those stationary exercise bikes? Oh well. Don't worry OP. I'm sure you look just fine. :) Maybe because of the fact that she's a child, she might think all adults are bigger.

Tell her you'd rather ride a fat girls bike than an ugly baby bike. Then kick the bike over.. Make her cry >:D o_o uhh, or, you know, you could still teach her but accidentally let go of the handle bars when she's near a street. Why am I do violent?! D: just don't teach her, FYL OP.

How old is your niece? If she's just now taking off her training wheels, I would assume she's young. She's probably not using an adult-sized bike. If that's the case, there's no reason to sulk. Of course you'll look "fat" on a child's bike; in that sense, you deserve it. Still, no need to take the comment to heart. Kids say rude things a lot. It doesn't make them right. I agree with some of the above though; it sounds like she could use more discipline. Good opportunity to nag your brother or sister! x)

She's just calling it as she sees it

I' d just leave her there without training wheels.. and with no way home... Lol.

Funny, aren't you a little kid too? xD

They speak what is on thier mind..

hahahaha sweet kid!

I see a diet in your future

So I read in some pretentious asswipe's bio not to confuse you for a nun. What's all that about?