The source continued: "Mike was a lovely, gentle, softly spoken old man.
"He was always happy to be asked about Meghan, but whenever he spoke to anyone he mainly wanted to talk about his late wife - he loved her so much."
The 82-year-old had moved to live in a trailer park community after his wife's passing.
The former diplomat had even helped Meghan a little in her earlier years.
According to the source, Megan was looking to a career in international relations, so Mike secured her an internship as a junior press officer in the American embassy in Argentina.
It's no secret that Meghan's relationship with her father Thomas and wider family on his side isn't straightforward.
It's understood Mike was also estranged from Meghan at the same time as her father.
Speaking to The Express last year, Mike sided with Thomas in the ongoing saga, explaining that he wished his brother could meet Meghan and Harry's son, Archie.
"Tom should be speaking to his daughter and his newest grandson," he said at the time.
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The death comes as Prince Harry has travelled to London to attend the grand unveiling of Princess Diana's statue, taking place on what would have been her 60th birthday.
The Prince has left his wife and their two children, Archie and newborn baby girl Lilibet, back in the US, where Meghan is on official maternity leave.
It is unknown if the Duchess of Sussex will publicly comment on her uncle's death. Given her preference for privacy, we imagine the death will be mourned privately by the 39-year-old.
This article originally appeared on our sister site, Now To Love.
