Reminds me of something that happened between my dad and I except it ended up just being a miscommunication.
When I was 14, my grandparents gave me a $100 bill for 8th grade graduation. My dad offered to keep it safe since I wasn't at home and didn't carry a wallet all the time, so I gave it to him. When we got home a few days later, I asked if I could have it back to put in my wallet. He was just like, "But didn't I give it to you?" I just said "No..." However, he didn't have a random $100 to give to me. And he still didn't for several months.
But on my 15th birthday, I got a PS3, which was supposed to be an extra extra special gift on the deal that I would just forgive the $100 debt. I was happy though and probably would've used it towards a PS3, so I was cool with it. Almost three years later, I was cleaning under my bed and found an unfamiliar envelope. I opened it and found the lost $100 bill. But since I am a decent person unlike the majority of the forum population, I gave it to my dad.