YOU SAID:
my grandma is pregnant with sons child
INTO JAPANESE
私の祖母は息子の子供を妊娠しています
BACK INTO ENGLISH
my grandmother is pregnant with my son's child
INTO JAPANESE
私の祖母は私の息子の子供を妊娠しています
BACK INTO ENGLISH
my grandmother is pregnant with my son's child
You've done this before, haven't you.