is my white molly pregnant, when is she going to drop the babies?
Is she a ballon molly?
When her belly gets large enough that when looking at her head-on, the top makes a sharp angle from her midsection, she's very close, maybe a day or so. From the side, her belly will look distinctly separate from the rest of her. It appears the second picture shows well what I'm trying to describe.
You should decide if you want to put her in a breeding pen, put up a tank dividing screen or keep her as is. Mine did fine in a pen, but some Moms get antsy. Just so you know, if you leave her out, the other guy in photo 2 will eat the fry as they are born.
Once she's more square then round. Looks close! They often drop at night so be careful to havve hiding spots for the fry. Congrats.