The base model Kindle is $10 less than the base model of Nook or Kobo. And Amazon has a reputation for repeatedly replacing cracked eInk screens, up to the one year warranty expiration (although googling shows that the other brands are also known to replace cracked eInk screens -- policies for cracked color screens are less generous).
Plus with Kindle:
-- Stable software
-- Brand name American kids tend to be impressed by
-- Rudimentary browser (works for reading news web sites like twp.com that, if a child was interested, will IMHO increase store of knowledge more than fiction)
-- Sometimes, but not now, bundled at stores like Staples with a $25 gift card
Cons:
-- Lack of touch screen or keyboard makes it a little harder to use (although this also makes it harder to use for purposes other than reading)
-- Lack of ePub support means slightly fewer public library borrowing options (incompatible with 3M Cloud Library)
-- $30 extra for model without advertising
At her age, I would have been happiest with this, but, then, I was and am a newspaper reader:
http://www.ebay.com/itm/Amazon-Kindl...item4d0ad0c46f
P.S. Looking at my last link, the item description is not 100 percent correct (does not have the "Pearl" screen). But I have purchased from this vendor without a problem.