Wonderful concept, very heartwarming.
Amazing visuals, fantastic job on making a cozy and cohesive world. I also had a bit of trouble with the riddles since I was triple checking the grandmother's notes for the flowers, and not directly the flower entries. Even so I got the flower for "solving the riddle" before the riddle had been solved and another one in it's place? Probably the code is crossed. Adding a glossary book/icon to fast-reference could help a lot. Seeing the flowers back at home was very nice! The song loop was a bit short but not a big issue.
The story was very charming and uplifting. Loved learning about the town and family little by little and contributing to a happy ending. Grandma felt very welcoming, and the birb was the best character.