I think they have to work it out on their own! Just warning, might be better to give Friday the attention first, then Ivy second, that way Ivy will know her position in the pack. Also DO NOT FEED THEM IN THE SAME ROOM! AND DO NOT LEAVE FOOD< TREATS LAYING ABOUT!  DO NOT LEAVE TOYS LAYING ABOUT EITHER< especially not Friday's toys! I feed my dogs in their kennels and toys are brought out at play time only.
Hazelanne