Not to be outdone by pregnant sister Kourtney, 29-year-old reality TV star Khloe Kardashian has decided to exchange wedding rings with LA Laker Lamar Odom this Sunday, just weeks after getting together.

A source says  the couple went ring shopping in Los Angeles over the weekend, and Odom bought Khloe a ring she liked on the spot. "She's not wearing it yet because it is being resized," says the source.

The radiant-cut pave set diamond engagement ring is worth $850,000 and was given to the oldest Kardashian sister only a month and a half of dating Odom

According to E! News, many of the wedding guests have already been informed of the celebration via telephone, with formal invites to follow this week - but the future bride has yet to confirm or deny the reports.

On September 4, Khloe confirmed she was dating Odom. According to older sister Kim: "They're very, very happy. They've been together a few weeks, and are literally inseparable."

Although the pair has only spent six weeks together, they are hoping to get married and have a honeymoon before Odom begins training camp with the Lakers this fall.

It is rumored that the many, but not all of the Lakers team was invited to the still secret wedding. Whether or not this is true, remains to be seen.

The news of the nuptials comes mere weeks after another Kourtney Kardashian announced she was pregnant with her on-again/off-again boyfriend, Scott Disick.

It really is hard keeping up with those Kardashians after all.