You referenced a period of seven years between crisis of a relative in your post. May be more than coincidence.
Remember old movie about Seven Year Itch? Ever hear that the body replaces all its cells in seven year cycles? Would you doubt that a person goes through multiple life stages although only certain 'major' transitions are noticed. They often occur as someone approaches the decade birthdays, 30, 40, and 50 but rarely much after 55.
MLC Trivia, or just trivial urban myths? Who really cares, we got nothing better to worry about, right?