If she is, they're probably just waiting until they're out of the first trimester. Something like 1 in 4 pregnancies are miscarried in the first trimester. More often than not, the woman doesn't even know she's pregnant and just mistakes it for a period. But miscarriages are crazy common. She if she's pregnant, they're probably just waiting until they're in the safe zone before telling people. That's what most couples do, at least.
She is obviously pregnant but It's a black thing to deny pregnancy till you're closer to due date for safety.
Wait what? What does it have to do with being black? It's not a black thing. Most women wait until they're at least 12 weeks in, and have entered their second trimester.