Beyonce Knowles - Beyonce Showered With Birthday Wishes

The Single Ladies hitmaker's friends and relatives took over her official website on Tuesday and secretly posted handwritten notes to mark the pop star's milestone.

Sister Solange wrote, "Dear Big Sis, There is no one like you in the world, of all of your mind blowing achievements the one that first comes to mind is your kindness. Your sense of selflessness, consideration of other people's well being and your beautiful generosity are all things that make me so proud be your sister and your friend."

And her fashion designer mum, Tina Knowles, added, "God blessed me with one of the greatest gifts in my life on September 4th, 1981. Happy Birthday, Love Mom."

Several of her nieces and nephews also contributed to the site, as well as her husband Jay Z's mother, Gloria Carter, who wrote, "You came into my life a sweet Southern girl... You've blossomed into an amazing woman. I admire how you remain grounded and humble, and haven't let success change the person that you are."

Williams added, "Happy birthday to youuu!! I love you so very much. I am so thankful you're in my life," and Iron Man star Paltrow, her husband Coldplay frontman Chris Martin, and their two kids wrote, "For dear sweet BB on the occasion of her 31st birthday... We love you so very much. Love, Gwyneth, Chris, Apple and Moses".