The reality star is expecting a son with her husband, Travis Barker.
"Travis is constantly checking in on her and making sure she's feeling OK," the source says of Travis Barker, Kardashian's husband and the drummer of Blink-182, who rushed home from tour to be by his wife's side amid her health scare.
Now, though, Barker is back on tour while Kardashian is home missing him. The feeling goes both ways, with the source telling ET that Barker "can't wait to be home with her and is so grateful that she's doing well and that their future baby is healthy."
While she rests up at home, the source says "Kourtney is focusing on taking care of herself and making sure everyone in her family is feeling good across the board."
"Travis and Kourtney are very united, their kids are getting along, and everyone is excited for the baby to arrive," the source adds of the couple, who already have six kids between them.
Kardashian shares Mason, 13, Penelope, 10, and Reign, 8, with her ex, Scott Disick. Barker has Alabama, 17, and Landon, 19, with his ex-wife, Shanna Moakler, and is stepdad to her eldest child, 24-year-old Atiana.
"As someone who has had three really easy pregnancies in the past, I wasn't prepared for the fear of rushing into urgent fetal surgery," she wrote in part. "I don't think anyone who hasn’t been through a similar situation can begin to understand that feeling of fear. I have a whole new understanding and respect for the mamas who have had to fight for their babies while pregnant. Praise be to God. Walking out of the hospital with my baby boy in my tummy and safe was the truest blessing."