Currently I have 1 CRS and 1 black diamond pregnant. So is it a guarantee that there will be small shrimps coming out?

Other told me that the female will lay out the eggs after that, then the male shrimp will fertile the eggs. Is this true? What happen if my male shrimps refuse to fertile the eggs? THEN.....No small shrimps????? OMG!!!

Anybody who has the experience? Do give me some feedback, thanks