From August 28, 2020 (Princess Diana died August 1997):

Princess Diana took a fridge filled with her own blood when she went abroad in case she suffered any medical problems, including being attacked.

Her former private secretary Patrick Jephson explained that he and the rest of the security team also had their blood types checked to see if they were a match in case she ever needed it.

He claims the extreme measures were necessary as Diana was "quite often under threat".

And Diana wasn't the only one with this blood type, as the Queen and Prince Charles also carry spare blood with them in case of an emergency.

Jephson said: “Particularly when we were abroad or in the developing world, we would carry a little refrigerator full of spare supplies of Diana’s blood", reports the Daily Star.

https://www.mirror.co.uk/news/uk-news/princess-diana-fridge-full-blood-22593439

This is not as odd as it might seem at first since Rh- individuals must receive infusions of Rh- blood, which is relatively rare compared to Rh+ blood types.

===

Princess Diana had O- blood (Rh negative). Queen Elizabeth, Princes Charles, William and Harry are also part of the club. (if both parents are Rh- their offspring will be also).

Rh- blood (especially O-) is so often found running in the veins of a royal family and their descendants, it was named the 'Royal Blood'. Sometimes you will hear Royals referred to as "blue bloods" or "pure bloods" (i.e., no contamination from Rhesus monkey genetic material). This corresponds to the commonly observed care royal families use when selecting mates and for breeding purposes. The need to keep the monarchy in the "family", and keep the royal line pure, even when biological problems of inbreeding result. But it also indicates a cult-like belief system, an occult superstitious belief that their ancestry can be traced back to "The Gods," and so they themselves are also god-like or even gods themselves.

And this is what the cultists believe:

Adam was to rule this world but when asked to bow down to him Satan refused saying “this newly created being was younger than I” and he would not do it even at the behest of Michael. Satan set out to take Adam’s throne which he managed to do by seducing Adam’s wife Eve but did not touch Adam.

The result was Eve’s first Child Cain would rule over all Adam and Eve’s children but Cain became wrathful when his younger step brother’s offering was accepted but not his. When Abel explained to Cain that his offering wasn’t accepted because his heart wasn’t pure Cain struck him down. Abel knew Cain was eating his sheep because Cain was clothed in their pelts.

Satan and his Angels fell because they didn’t keep their Heavenly Order. They traded their Heavenly abode to take Adam’s throne. They did so through sexual intercourse with woman. They became locked into flesh bodies because of their coveting women. They also created an addition race of Hybrids that were blended with animals (Rh +).

Satan's/Cain's descendants are part Angel, part human and are sometimes called Demons. It is important to them maintain their "pure" bloodline, with Eve's Rh- blood. They sometimes call themselves sons of Cain. For example, John McCain means John "son of" Cain.