Star Tracker: Mario Lopez, Paulina Rubio, Shakira and more!

Paulina Rubio’s influence runs deep on Twitter. Recently, she tweeted a message in an effort to find a liver transplant donor for her friend in Argentina. As the messages became more urgent and Juanes retweeted, Rubio’s fans showed their support and her friend received the transplant.

—Colombian salsero Joe Arroyo has been hospitalized in critical condition in intensive care. In response, fellow-Colombian singer Shakira tweeted out a prayer of good wishes saying, “Joe, your country and all who love and adore you are asking for your health. Get well soon.”

Mario Lopez is releasing his own children’s book in September. The title of the book is Mario and Baby Gia, named after his daughter Gia Francesca.

—Apparently, Selena Gomez is so bad at playing polo that the writers of her new film Monte Carlo had to rewrite a scene for her.