In a preview clip for an upcoming episode of Keeping Up With The Kardashians, we see Scott, 32, appearing out of nowhere in Kourtney's house… while she's chatting with sister Kim Kardasihan West about whether she can forgive him.
A stunned Kim says: "I am in shock. I haven't seen him in so long. He obviously spent the night and Kourtney didn't tell me he was there."
She then adds: "I thought Kourtney was strong and firm but now, are they back together? I just don't understand."
Kourtney, 36, dumped Scott in July after reportedly growing tired of his constant partying. It's believed the last straw was pictures of him partying in Monte Carlo with another woman.
Since then, Scott has completed a rehab programme and is reportedly keen to make amends with everyone he has hurt in the past.
Kourtney and Scott were together nine years and have three kids: Mason, five, Penelope, three, and Reign, 11 months.
Keeping Up With The Kardashians airs Sundays on E!
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