When I saw the large floral spray brooch in your fist picture (13Sep1952) and again in #5 (12Jul1949) the first thing that popped into my mind was the "brooch" the current Queen wore to a cocktail party aboard HMS Illustrious in Turkey.

I put brooch in quotes because many feel that this is not a brooch but applique.

I am wondering if the top portion of QEQM's brooch matches??

It is hard to tell but the basic shape seems to be the same with the central flower surrounded by trailing leaves

Here is a link to the item I mean:

https://www.gettyimages.ca/detail/news-photo/queen-elizabeth-ll-attends-a-cocktail-party-on-board-hms-news-photo/83245714