Your sister might sometimes annoy the heck out of you but she deserves a pleasant iRobot Roomba gift on her birthday. With a 3-stage cleaning system and dual multi-surface brushes, this beast of a house cleaner will pick up everything from the smallest to the biggest debris. This Roomba has all the cutting-edge technologies like patented dirt detect sensors and other intelligent sensors that automatically push it to work harder than ever. And after 90 minutes of hard work, this iRobot Roomba rests and recharges itself automatically. Your sister will forever thank you for this!