While some speculated that Demi Moore may be on the verge of another trip to rehab, according to our inside sources, the only substances she is addicted to are age-fighting ones — Restylane, Perlane, Dysport and Botox. While in town during Art Basel, the 50-year-old Moore made repeated visits to popular NYC and Coral Gables-based cosmetic dermatologist, Dr. Frederic Brandt.

As for the rumors she was shacking up with the 26-year-old art dealer Vito Schnabel at the W South Beach, those weren’t true either. Moore stayed at Alex Rodriguez’s house, Miami’s own Hotel California for the bona fide A-listers. For a second we wondered if A-Rod and Moore were an item. “No, no, they’re not together at all,” says our mole. As for the ex-Mrs. Kutcher’s behavior, that’s an exaggeration, too. “The only thing weird about her, and it’s not even that weird considering her age and considering her love of younger men,” says the snitch, “is that she is absolutely, completely obsessed with her weight.” Or lack thereof.

In town for the Y-100 Jingle Ball, Justin Bieber was seen having lunch late Monday at Prime 112 with some of the members of hot hip hop record label Cash Money. Because Bieber arrived after lunch service had already stopped, the restaurant kept the kitchen open to feed the growing boy/pop star. Having dinner in the restaurant later that night were the recently ubiquitous Flo Rida and Fabolous.

Beyonce and Jay-Z spent Tuesday afternoon at Aventura Mall where they were seen shopping at LeBron James’s store Unknwn.

Will Smith, son Trey and Puff Daddy’s mother Janice Combs had dinner Sunday night at Bella Beach Club in Sunny Isles.

Hanging around Fort Lauderdale after Aerosmith’s show at the BB&T Center, Steven Tyler had dinner Monday night at Steak 954 with two friends. The group let their server select the first two courses and then nibbled on oysters, stone crabs and big eye tuna & foie gras tacos. For the main course, the lanky Tyler chose the bone-in filet with mac and cheese.

Before his team beat the Miami Heat, Golden State Warriors’ player Harrison Barnes made a special visit Tuesday to the patients and families at Miami Children’s Hospital. Barnes passed out autographed Golden State warriors shirts and spent time with children in the MCH Cancer Center. This was his second visit to the hospital.

Gloria Estefan and daughter Emily enjoyed lunch Tuesday at the newly opened Serafina Dream South Beach.