Scott Disick's ex-love Kourtney Kardashian has met with top Hollywood divorce attorney, "disso queen" Laura Wasser, and she wants sole custody of their three kids, a source confirms to Us Weekly exclusively -- find out more about Kourtney's legal concerns. Credit: Gustavo Caballero/Getty Images; Imeh Akpanudosen/Getty Images

Step one. Kourtney Kardashian has met with top Hollywood divorce attorney, "disso queen" Laura Wasser, following her high-profile split from Scott Disick -- and it's because she's seeking sole custody of their kids, a source confirms exclusively to Us Weekly.

While Kardashian and Disick were not married, the couple of nine years shares three young children, Mason, 5, Penelope, 3, and Reign, 7 months. A source tells Us in the new issue that Kourtney, 36, is determined to protect her kids from Disick's downward spiral, fueled by booze, drugs, and other vices.

Insiders previously revealed to Us that Kardashian first started exploring her legal options -- including a consultation with the "Disso Queen" -- during the weekend of July 4, days before Us confirmed that she and Disick were done.

On Monday, July 20, Kardashian paid yet another visit to the top Hollywood attorney's office building in L.A.'s Century City nabe. "She met with Laura Wasser again," a Kardashian pal tells Us. "And is going to seek sole custody of the kids."

She and Disick currently do not have a formal custody arrangement, but sources tell Us a battle over the kids would be surprising. "Scott's friends don't think he'll challenge Kourtney," one insider tells Us, while another adds that the self-proclaimed Lord "doesn't act like a dad at all when he's partying."

Kourtney wouldn't be the first Kardashian to become well acquainted with Wasser, who's worked on high-profile cases including those of Kim and Khloe Kardashian.

In February 2013, while Kim was expecting her first child with Kanye West, Wasser famously held Kim's hand while heading into a meeting with Kris Humphries. (While Kim and Kris' marriage lasted 72 days, their divorce process was long and drawn out. Kim filed papers in October 2011, and the two finally reached a settlement in April 2013.)

Later that year, in December, Wasser filed divorce documents on behalf of Khloe in her split from Lamar Odom. (Coincidentally, as reported on Tuesday, July 21, both Odom and Khloe have finally signed the papers and their divorce is nearly finalized.)

Wasser has also famously worked with stars like Angelina Jolie, Ryan Reynolds, Ashton Kutcher, and many more high-profile names in their dissolution of marriages.

Amidst Kourtney's meetings with legal counsel, Disick was photographed driving in Beverly Hills in the early hours of Wednesday morning looking exhausted. It remains unclear whether he's reunited with his children in his return to L.A.

"She knows being with [Laura] is what's in their best interest," the Kardashian pal tells Us of the kids. "There's no turning back now and she is going full steam ahead with figuring out an agreement."

For more details on Kourtney's custody showdown and more tidbits on Scott's hard-partying habits, pick up the Aug. 3 issue of Us Weekly.

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