Jennifer Gates and Nayel Nassar.Photo: nayel nassar/ instagram

Jennifer Gates and Nayel Nassar

Jennifer Gates' wedding this weekend will be one for the books.

Jennifer, the eldest daughter ofBill GatesandMelinda French Gates, is getting married this weekend toNayel Nassarin Westchester County, New York, a source tells PEOPLE.

“It will be a big wedding,” the source says.

“There is a lot of security, so no doubt there will be prominent guests,” the source adds. “Workers have been busy all week. They are setting up both indoor and outdoor areas. They are building several temporary steel and glass pavilions.”

Jennifer, 25, has turned to her mother to help her get ready for the big day.

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“Jennifer is very close with her mom,” the source says. “Melinda is ahuge part of the wedding preparations.”

Jennifer and Melinda, 57, were spotted kicking off the pre-wedding celebrations on Wednesday,stepping out together in New York City. The pair were seen arriving at the Plaza Hotel, where Melinda wore a monochromatic pink outfit while Jennifer donned a white dress.

(L-R) Melinda French Gates and Jennifer Gates.splash News

Melinda and Jennifer Gates

“Jennifer and Nayel are both in N.Y.C.,” adds the source. “They both seem very excited about their wedding week.”

Bill, 65, has also arrived in New York City ahead of the big day. The billionaire Microsoft co-founder was photographed exiting a helicopter with some family and friends on Thursday.

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Bill Gates.Elder Ordonez/SplashNews.com

Bill Gates is all smiles with family members while arriving at the Heliport in New York City

Jennifer, who called her parents' separation a"challenging" time for their family, has spent time in recent months with both her mother and father.

“Thank you for thisincredibly special celebration, @melindafrenchgates,” the Stanford graduatewrotealongside a series of photos, including one of the mother daughter pair.

“So deeply grateful for all the amazing women in my life who advise, support, and uplift me. 🥂 to this new chapter!” Jennifer added.

Jennifer Gates and Melinda French Gates.Jennifer Gates Instagram

Jennifer Gates Instagram

Jennifer, who is currently an MD Candidate at Icahn School of Medicine at Mount Sinai, also shared a smiling photo with her father back in May.

“Nothing better than quality time with family members,” she captioned the snap.

source: people.com