It happens, my kids had 2 for 2011 christmas.
And we didn't find anymore all last year until November, when i found 2 more. Then they got 6 for 2012 Christmas.
Today even I have 4 dolls (mine mine), my daughters dolls don't fit on their shelves and I had to bring more shelves. And it's only been 5 months of 2013!
YEY!