Rihanna and Chris Brown are moving in together. The "Umbrella" singer - who has been looking at multi-million dollar mansions in the Hollywood Hills area of Los Angeles - is planning to set up home with Chris as soon as she chooses a property.

X17 reports: "Once Rihanna moves in to her new pad, Chris Brown will be joining her!"

Rihanna has been house hunting in the Hollywood Hills. The "Take a Bow" singer reportedly spent Monday looking at properties in the same exclusive area of Los Angeles where celebrities such as Leonardo DiCaprio, Nicole Richie and Cameron Diaz live, according to X17Online.

Rihanna, 21, is also believed to have viewed Christina Aguilera's former Hollywood home, which is closer to the city's shops and clubs than her present house in the quiet neighborhood of Los Feliz.

Nicole Richie threw a huge 30th birthday party for her rocker boyfriend Joel Madden this week. The socialite held the bash on the private terrace of the Sunset Tower hotel in Hollywood. She invited around 35 of their friends to celebrate with Joel - who reached the landmark age on March 11.

An onlooker said: "There was a lot of laughing and even some speeches. Nicole and Joel were nestled in the center of the big group and looked as happy as they could be to be celebrating with their friends. They were beaming in the soft terrace lighting."

Nicole Richie is unsure whether she will marry Joel Madden. The 27-year-old star - who has 14-month old daughter Harlow with Joel, and is currently expecting her second child with him - is content with her relationship and refuses to plan too far ahead.

She said: "I don't know about the future. I make it a custom not to plan the future. I may plan to and I may not."

Paris Hilton rocked her 28th birthday bash at the Hard Rock hotel's signature hot spot Body English with a new man on her arm and new projects on the docket. She was accompanied by new-ish flame, former "The Hills" alum Doug Reinhart, who seemed like a natural in his role. The pair has "known each other for a couple of years now" and appeared rather smitten with one another.

The birthday girl was preceded on the pink carpet by E! News notables Ben Lyons and Catt Sadler in addition to the up-and-coming music duo Chester French.

Nicole Richie thinks Joel Madden is a "superdad." The "Simple Life" star - who has a one-year-old daughter, Harlow, with the Good Charlotte rocker - insists he is the best father she has ever seen.

She said: "When you're parents you have to make every decision together, so you become a team. I can wholeheartedly say that he's the best dad I've ever seen."