My brother and grandma had a sort of similar thing going for a couple of weeks 60ish years ago. He needed to send her a letter, but had no stamp so he taped a nickle the envelope. It arrived with the nickle canceled! She took the nickle off the envelope and used it to send a response. Alas, it arrived at his dorm with the nickle replaced by an uncancelled stamp. Which he soaked off and used to send her a letter. THAT one got cancelled.
I strongly suspect the story is better than whatever they chose to tell each other inside the envelopes.
My brother and grandma had a sort of similar thing going for a couple of weeks 60ish years ago. He needed to send her a letter, but had no stamp so he taped a nickle the envelope. It arrived with the nickle canceled! She took the nickle off the envelope and used it to send a response. Alas, it arrived at his dorm with the nickle replaced by an uncancelled stamp. Which he soaked off and used to send her a letter. THAT one got cancelled.
I strongly suspect the story is better than whatever they chose to tell each other inside the envelopes.