I don't think so! I haven't read either yet -they are waiting at the self until I finish lady of the rivers- but judging from all the other books -I've read the entire Tudor court collection-, each book is independent, it has its own beginning and end, which allows you to skip steps. I mean, I read the other Boleyn girl, before the constant princess, no problem at all! Same goes for reading the virgin's lover before the queen's fool! I think the rule applies to all the books ;)