Instead of working on specific memories, I decided to remember family moments that happened every year : Summer holidays, Christmas and Easter. For the end result, I wanted to have only one scene that would show those three memories one by one in one smooth shot. To achieve that in a believable way, I chose a physical diorama that would have the memories as miniatures, like a person could craft similar objects as a way to remember their memories.
I used Blender to create the models of each scene. Most of the objects are plain and simple to enforce the "miniature" feeling, the diorama on the other end was made to be in contrast of those objects.
I used Substance Painter to create the textures. And just like the models, the diorama texture is the only one to be made to feel a real object, for the rest of them I used painting and procedural tools to achieve the hand-painted look that miniatures have.
The scene in Unity is quite simple : the three memories are side by side on their respective dioramas, each on a blank pillar above an ethereal sky. I then used Cinemachine to create the final video in one shot. There are three dolly tracks that move around each memory from Summer to Easter, with blending in between.