File:Harvest Moon- Sunshine Islands - Denny and Lanna - Proposal

Watch the first two events, then walk from Verdure Island to Sprout Island between 4PM and 7PM on a sunny day, in Year 4 or later.

Depending on your gender, Denny/Lanna must be at 8-9 hearts for this to trigger (alternatively, if you are married this can be triggered regardless of friendship).