Scott Disick Hits the Beach with 19-Year-Old Amelia Hamlin

Scott Disick can't stay single for very long ... and his latest fling is with a 19-year-old with some very famous parents.

Disick and Amelia Hamlin -- daughter of Lisa Rinna and Harry Hamlin -- were arm-on-shoulder Monday in Santa Barbara. The two recently hung out at a Halloween party ... so it appears things have gotten way past the friend zone.

As you know, 37-year-old Disick recently split with 22-year-old Sofia Richie after dating for 3 years. Sofia's dad, of course, is none other than Lionel Richie ... so, more famous parents.

Scott and Kourtney Kardashian -- with whom he shares 3 kids -- recently took a few trips together ... but we're told the two were strictly co-parenting and having fun together as friends.

Disick had a brief stint in rehab earlier this year --  the word was he was dealing with some lingering emotional traumas including his parents' deaths.

TMZ broke the story ... he checked out early after a photo of him inside the facility was leaked to a media outlet.