Nicole Richie and Joel Madden left their little ones at home yesterday as they headed out for lunch, but fun times were in store since it was also Harlow's second birthday! We marked Harlow's milestone by taking a look back at her first years with a special slideshow. Nicole woke up early to set up surprises for their daughter, before jokingly tweeting that Harlow and Mary J. Blige were having a joint birthday party. Joel, meanwhile, showed off his fatherly love by writing, "Happy Birthday to the most beautiful little girl in the world. Harlow makes me proud every. Single. Day. I'm blessed." Aww.