Ever wonder how today's hottest celebs spend the holidays each year? ET talks to Reese Witherspoon, the Jonas Brothers, Julianne Hough and other big stars about their holiday traditions -- and we find out which star plans to sneak into theaters on Christmas Day to watch her own film!

"Christmas Eve, I'd say, is almost even better than Christmas because every year we go ice skating, have dinner, come home, get our hot chocolate, watch a movie ... and then we get to open up one present," pro dancer turned country music singer Julianne Hough tells ET about her holiday traditions.

Reese Witherspoon tells ET she loves to spend the holidays singing Christmas carols, while the Jonas Brothers describe their family's organized gift-opening traditions. Adam Sandler playfully tells ET his family's holiday traditions include fighting and eating.

ET also learns what Scarlett Johansson, Jessica Biel, Samuel L. Jackson, Kate Winslet and other big stars have planned for the holidays. Click to see which beautiful actress is heading to her own movie on Christmas Day!