Nicole Richie made for a cute White Rabbit as she brought Tinkerbell Harlow to a Halloween party on Saturday. With Joel off in Australia performing with Benji, Nicole was on holiday duty with their two kids, though Sparrow didn't get dressed up for the festivities with his mom and sister. Nicole had said that she wanted Harlow to dress up as a character from Alice in Wonderland as well, but the two-year-old had her heart set on Tinkerbell. While Nicole's costume was perfectly coordinated, we still couldn't help but notice what looks like a diamond band on her ring finger. Joel denied the rumors that they secretly tied the knot earlier this month, so perhaps she's just wearing it to signify their commitment.