This reminds me of another point -- wasn't Prince Philip (and only Prince Philip) the one who got the worst deal -- as far as not ever getting to be the King of England, due to the Queen's ridiculously long reign/lifespan? I don't know much about the British Royal Family, so I can't say for sure.
I almost sympathize with that poor b****** Prince Philip; it kind of does seem like the Queen will never die, doesn't it?
I think the British regularly joke about how old the Queen is, how she's been reigning for 100 years, etc.
To add to and clarify Nadir's point, reigning queens' spouses are usually referred to as "prince consort" because if they were called king then people would think
they were the one in charge. Prince Philip is sort for Prince-Consort Philip. Easy mistake to make though, because their son Prince Charles is also quite old at this point, so any "old prince" might seem like the heir at a glance.