Has anyone else become hysterical during woohoo with the grim reaper?

So I have been romancing grim so that I can have a baby with the the grim born trait, and for some reason every time my sim got anywhere near grim they would become very playful, and then when they would get into bed to try for a baby they instantly became hysterical… I was so stressed out about them dying midway through woohoo but they thankfully survived! 

Has anyone else experienced this sort of situation, or is it just me?