Use the chart as a conversation, not a test
Begin with the person your relative knows best. Leave unknown boxes blank and write “family recollection” beside details that still need a record. A respectful pause is better than forcing an answer.
Keep online-tree exports separate
If you work in Ancestry or Family Tree Maker, preserve a dated export or full backup before reorganizing. Then use this simple chart for the branch you want to discuss. See the guides to turn an Ancestry tree into a book and back up Family Tree Maker with media.