It appears that Caroline herself has sold out on AG's website. She is no longer on the Beforever list on the left side of AG's website. If you search 'Caroline' on their website, though, you can still buy a few things.
Available Items On The Website (as of Dec. 26):
Lacy Ribbon Top (for girls)
Cuffed Jeggings (for girls)
Caroline's Nightgown For Girls
Caroline Mini Doll