Nah, not just the twins, it's the whole family of Celine's! The twins, delivered in last October 2010 were wrapped in white blankies (I think) with the rest of the family members at the back.
This is the photo attached to the holiday greeting cards that were sent to the employees of Caesars Palace, where she'll be performing at starting 15 March 2011.
She wrote that she, Rene her husband and son- Rene-Charles;
"are looking forward to returning to Las Vegas, and with the twins Nelson and Eddy, there's going to be a lot going on around our house!!!!"
Source from The Insider