Donald Trump usually isn’t one to show too much emotion, but the big-wig businessman was clearly moved by Christina Aguilera’s live performance at the Nakheel and Trump Organization party on Saturday night in Los Angeles to celebrate the Trump International Tower in Dubai.

The Donald looked spellbound by the striking songstress, shaking his head in disbelief as she showed off her four-octave range in an emotional rendition of her 2003 hit “Beautiful." (It was hard to believe that Aguilera had a baby earlier this year judging by her itty-bitty waistline.)

But as much as Trump clearly has a thing for the 27-year-old, she was pretty daunted by him as well.

“On a night like this I definitely get those pre-performance butterflies. I think there’d be something wrong if I didn’t get them just a little bit — it’s Mr. Trump,” she told Pop Tarts with a smile before her showdown. “Tonight’s sort of more [of an] intimate setting, just with a very stripped down band of mine, so it should be fun.”

Aguilera also said the most challenging part of being successful in the entertainment industry is getting rid of the bad apples.

“In this business it gets crazy — the people that you sort of have to weed through with bad intentions or ulterior motives — but you have to trust your instincts,” she said. “In the end, know what you’re in it for and it’s the love of music and the love of what I do, so I just have fun with it and really continue to try and soul search and be myself continuously through and through.”

Christina stayed on at the super-swanky soiree right up until the end, rubbing shoulders with the likes of Ivanka Trump, Lucy Liu, Orlando Bloom, Aaron Eckhart, Hayden Panettiere, Diddy, Ali Larter, DJ Pete Wentz (who refused to discuss wife Ashlee Simpson) as well as Deryck Whibley and wife Avril Lavigne (who was also partying up with her new BFF Ali Sims.)

Hilary Swank was also there, fresh from her flight in from South Africa after wrapping “Amelia Earhart” and sporting a new, very short blond crop.

“I didn’t find cutting my hair that shocking,” Swank said. “I think a lot of people wish that they could cut their hair and had the guts to do it. Everyone says it’s so courageous — I’m like, not really, it’s my job.”

Lindsay Lohan Disses $10,000 Birthday Gift, Ronson Gets Served at Party

Lindsay Lohan is a movie star, but it seems the starlet has a sentiment for the small things in life.

The starlet recently received quite a pricey package for her 22nd birthday, which we’re told was valued at around $10,000 and consisted of high-end bags, clothes and jewelry.

But an insider told Pop Tarts that Lohan has refused to take the stuff out of the box, let alone be seen wearing any of it. Why? The friend/sender didn’t bother to put in a birthday card and Li-Lo was peeved.

“She’ll probably just end up giving the stuff away," our source said. "That’s not something she will just get over.”

Meanwhile, Pop Tarts spotted Linds hanging out by the DJ booth with girlfriend Samantha Ronson, who was working the decks at last Thursday’s Vinyl Vixen party at Whiskey Blue. Typically, Lindsay refused to be photographed and Ronson made sure to keep a close eye on her as numerous male friends made their way over to say hi.

And although Sam put on a good show until the early hours, the night kicked off with an interesting start when one of blogger Perez Hilton’s peeps served her with another wad of legal papers as she walked inside.

Ronson filed a $20 million lawsuit against the celeb blogger for defamation after he repeated a report that she stashed the cocaine that was found in Lohan’s car after a crash. However, a judge dismissed the case in November and according to Perez’s rep, Ronson was ordered to pay his legal fees which she hasn’t done yet and that was the reason for her serving.

Kevin Federline Still in Love With Britney?

They’ve been through one of the most dramatic divorces and custody battles in Hollywood history, but apparently Kevin Federline still loves his former flame, Britney Spears.

According to an inside source, Federline is still very much in love with the pop princess, but doesn’t believe a reconciliation is possible.

“It was too hard for him to handle her,” the pal said. “He had to get out.”

One former flame Federline hasn’t been ignoring is the mother of his first two children, Shar Jackson. Kevin joined Shar on Friday night at Las Vegas hotspot Prive to celebrate her upcoming 32nd birthday, where the two took over the DJ booth and appeared to be getting along pretty sweetly as they joked with each other until the early hours. ...

Last time we caught up with K-Fed (a couple of weeks ago), he stayed mum on his next career move, but our source said he has been busy recording a new album in the studio and is working alongside Dr. Dre.

Meanwhile, Federline’s lawyer Mark Vincent Kaplan seems to be reaping the rewards of being a pseudo-celebrity thanks to his involvement in the high-profile custody battle against Spears. The balding attorney spent his Saturday evening all over (literally) a very beautiful, yet very young lady at Trump’s soiree and the two left hand in hand.

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