My molly had her first batch of fry on January 4, then the next February 10, so 37 days apart. She was skinny for all of 4-5 days and back to pudgy. She always looks about to pop and just when I think she can't get bigger, she does.
I say give it some time, I think I read it can be up to 45 days. I think average is a month.
My bettas: D'Argo + the girls Jullanar, Lalla, Razz, Rayleigh, Aviendha, Arya, & Lovelylocks
plus the other guys Toni, Eli, and Clinton (platy, guppy, and molly) a kuhli- Burt, 2 yoyos- Duncan and Ma, and otos, Laurel, Hardy, Larry, Curly, and Moe, plus the kitty, Clara the Impossible Girl.
SIP: Turk (teal VT), Azul (royal blue VT), Jerrica Benton (pink cambo CT), Lady Amalthea (blue cambo CT), and Jadzia Dax (blue VT)