Sydney Sweeney's New Lingerie Line Backed by Lauren Sanchez, Jeff Bezos

Now we know why Sydney Sweeney -- who had no obvious connection to Jeff Bezos or Lauren Sanchez Bezos -- was invited to their wedding ... it all has to do with $$$$$$$$$$$$$$.

Jeff and Lauren, along with tech mogul Michael Dell, plunked down $1 billion in a venture capital company called Coatue. A dude named Ben Schwerin is a partner in Coatue.

Well, the well-connected Schwerin is funding Sweeney's new lingerie line, according to Puck News, so therein lies the connection. Essentially, it looks like Coatue is backing Sydney and Jeff and Lauren are backing Coatue.

It's interesting ... we dug into Coatue's investment portfolio, and couldn't find anything related to beauty and fashion, so this is a left turn for the company.

Enter Lauren Sanchez Bezos ... sources with direct knowledge tell TMZ, Lauren is the one who was the driving force behind the new venture. She knows Schwerin well, and he introduced her to Sydney. She put her new hubby, Dell and Schwerin together to make the deal.

Sydney was a big hit with the guys who were also at the wedding, like Tom Brady and Orlando Bloom, who hung out with her at a fancy hotel.

And more dots are connected ... the first time we saw Lauren, Jeff and Sydney together was at this year's Vanity Fair Afterparty, where Jeff awkwardly posed with his then-fiancée, Sydney, Sofia Vergara and Jessica Alba.

Sydney may have given a sneak peek of her new venture, where she posed in lingerie with fashion model Amelie Tremblay.