It must be hard being the baby sister of one of the biggest-selling music artists of all time, and Solange Knowles is clearly feeling the heat.

A sour-faced Knowles appeared on the Las Vegas daytime FOX entertainment show "More" on Wednesday to promote her new album, "Sol-Angel & The Hadley St. Dreams," and was clearly peeved when the anchor introduced her as B's sister.

We're told that the publicity team behind the album has banned media outlets from even mentioning Solange's sister's name and under no circumstances were any Beyonce-related questions allowed. Oops.

But if that wasn't bad enough, the 22-year-old started the live satellite interview by flipping out and telling off the surprised anchor by referring to her as "unprofessional."

Click to watch.

Just minutes before her interview, the station ran a tease piece on the breaking news that the Vegas branch of Jay-Z's club 40/40 was officially closing down. So Solange started complaining about being linked to her "brother-in-law's establishment" until a producer interrupted and told her that the tease wasn't live and hadn't even run yet. Another oops!

Apparently, Knowles' peeps were apologetic about the diva-like outburst, although no official statement was made and a request for comment was not immediately returned.

A source close to Solange told Pop Tarts that the songstress hasn't really had any media training, is "coddled" by her label and is spoiled to the point that she gets whatever she wants.

We've also been warned that quite a few FOX outlets have gotten an attitude from Knowles as she apparently isn't a fan of the network, but is still willing to use us to promote her album. ...

But back to Jay-Z, it seems the closure of his 40/40 club comes as no surprise due to the numerous problems involving staffing and liquor licenses that the venue has encountered since it opened on Dec. 30 last year.

"A lot of things didn't add up. They got that liquor license oddly fast," a source said. "And in Vegas, if the staff aren't treated right, they just move to the next bar."

Super-Slim Jessica Alba Hangs at Hotspot Until the Early Hours

She is a brand new mama, but that isn't stopping Jessica Alba from having a hot night out.

Pop Tarts spies spotted the actress and her hubby, Cash Warren, out and about on a date night at hotspot The Standard on Sunset on Wednesday night.

We're told the totally makeup-free actress seems to have lost all those pregnancy pounds, and judging by the way the two were acting together (even sitting on the same side of the booth so they could be next to one another), being married hasn't taken the lust out of the love affair.

Eddie Murphy's Adults-Only Flight

Many of Hollywood's big-wigs are getting serious about environmental concerns. But clearly Eddie Murphy isn't one of them.

An insider told Pop Tarts that Murphy took a pack of pals for a family vacation in the Greek Isles this past weekend, only he insisted on chartering two private planes: one for the adults and the other for the kids. Even though there were only six adults in the 12-seater, the comedian wanted "privacy" for his mature friends.

But Tarts also has been told that it's one wild time in Greece as the "Daddy Daycare" star also flew out a bunch of other buddies on commercial airlines. The party pack is staying on a huge lavish yacht and even planning day trips to Athens on the private planes before returning to the States around Sept. 7 (although the youngsters are due back earlier).

Let's just hope they make it into the country without craziness this time. Apparently, when Murphy flew friends out of the country late last year (just before his quickie wedding), an arrest warrant was issued for a passenger on their return to Los Angeles.

Report: Roger Federer & Williams Sisters Out Drinking Before U.S. Open

Current U.S. Open titleholder Roger Federer as well as previous winners Venus and Serena Williams were reportedly sipping on something a little more than water at Wilson’s annual U.S. Open Party to kick off the tennis tournament at Mansion in NYC last weekend.

We’re told the threesome "very much enjoyed" their p.i.n.k vodka cocktails ahead of their big week. Doesn’t sound like ideal peak performance nutrition, but maybe it works well in relaxing those pre-game nerves. …

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