Thatcher is with Reagan in #17. In #22, it’s Queen Elizabeth II — or, as we know her here in Canada: Her Majesty Elizabeth the Second, by the Grace of God of the United Kingdom, Canada and Her other Realms and Territories Queen, Head of the Commonwealth, Defender of the Faith.
Pardon me. My browser didn't open the picture of Reagan with Queen Elizabeth. I only saw the one of him with Maggie Thatcher, and didn't notice that the poster was referring to the other pic.