Diana was wearing similar dress when she announced William's birth.

Diana was born in 1961. Rosemary's baby was written in 1967, movie in 1968.

Around that time there is this amous picture of Diana

A lot of people believe William is the product of centruries of breeding program (Rounde Table) to fuse all 13 bloodlines and hence the anti-christ.

Rothschilds have supposedly been inbreeding with British royalty and many of the princes are actually result of this. Princesses like Diana and Kate arent always willing participants and sometimes when they realise the true extent of the evilness they try to fight back and it results in their tragedies.

Just like all crimes are being "reenacted" in the current timeline - 9/11 -> Jan 6, AIDS -> Covid, Forever Wars -> Ukraine war etc, its quite possible that Kate is helping the WHs by "reenacting" this (maybe real, maybe fake) to catch whoever is involved in this.

Just a theory, but i think there is more than meets the eye