Ms. Paris and Mr. Paris have actually chosen two rings to celebrate their love, PEOPLE has learned. The bride-to-be picked out a 21-carat canary diamond as an "I Love You" ring and a white diamond engagement ring of at least 23 carats.
No big retail jewelry names were involved; the stones were purchased from a private dealer and will be set by a private designer – and the rings should be set and adorning Hilton's finger by later this week.
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Over Memorial Day weekend, Hilton "did a fun barbecue, and we all went over to Paris Latsis's house for the whole weekend," says pal Brian Long. "They had a giant trampoline in the backyard and hamburgers and hotdogs, and it was all of her close friends ... and that is where she announced (the engagement)."
Long considers Paris and Paris a good match. "She's amazingly happy. He is awesome. They met in December and have pretty much been together ever since then. He is nice and fun and totally makes her happy. Everyone likes him ... and he lets Paris be Paris."
Adds Johnson: "It is so sweet to see them together. She is so madly in love. I've seen her through her very first boyfriend in 7th grade, and I've never seen her this happy. (Latsis) is really her soulmate."
Hilton still hasn't announced when she'll have the wedding, but plans are underway to throw an engagement party in Latsis's homeland of Greece.
Meanwhile Paris, who recently said she would soon settle down and start a family, is making more headlines for her sexy Carl's Jr. ad. The controversial TV commercial, which has the bikini-clad socialite scrubbing down a Bentley before biting into a Spicy BBQ Six Dollar Burger and declaring, "That's hot," is set to expand beyond its West Coast broadcast zone into markets in the Midwest and Southeast.