Could this "friend" really fool her partner into believing she was pregnant? Like, one day she was pregnant and the next day she had a baby... how about the going to the hospital, giving birth, the postpartum parts of having a baby? Also, it looks like she was "expecting" a boy.
I had a family member faking a pregnancy when I was about 9 or 10. She did it all in front of me. She kind of had a "bump", but when she would go to the check-ups and come back with her hair done, her nails done, while I waited in the mall, by myself. It was pretty clear that she had not gone to any check-up. And then, I vividly remember her printing out ultrasound pictures, she would never bring it from the doctor, she would always print it out... at a public place. She bought everything for this baby, a crib, a stroller, clothes, diapers, she had a name picked out and then, a few months later, someone asked another family member how she was doing and the only response we got was "there's no baby", nothing else, nobody ever spoke about it ever again. This was 13/14 years ago, a few years later I got myself thinking about the ultrasound pictures and how I was always dropped off at the mall when she was at the check-ups and never allowed to go, and it all became pretty clear, she was faking it. When the "there's no baby" bomb was dropped, I was asked by the adults "well do you think she was pregnant?" and my answer was "yes, I saw her belly".
I was pretty messed up by the whole thing, I was very sad for a while because I believed that she had lost that baby and I felt so sad for her, but mostly because I already loved the baby and cared for the baby. A baby that never existed.
So, while I find it hard to believe that her partner wouldn't notice all the red flags, I also have to remember that 9-year-old me saw it all in front of my eyes and I didn't suspect anything, I was heavily manipulated and used as a alibi.