How to Chart the 'I'm My Own Grandpa' Family Tree
Map out the classic 'I'm My Own Grandpa' genealogical paradox chart step-by-step on a whiteboard with color-coded relationship lines and generational tiers.
This guide shows how to chart the 'i'm my own grandpa' family tree in 15-25 minutes. Start with establish base generations and the core couple; follow the safety notes and step checkpoints below.
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🧰 Required Tools & Equipment
- ✓ Whiteboard or large poster board
- ✓ 4 different colored dry-erase markers (black, blue, red, green)
- ✓ Ruler or straightedge
- ✓ Whiteboard eraser
📦 Materials & Supplies
- ✓ Color-coded sticky notes
- ✓ Genealogical relationship reference guide
⚠️ Safety Checkpoints & Warnings
- • Ensure dry-erase markers are used in a well-ventilated space to avoid inhaling solvent fumes.
- • Mount or secure the whiteboard firmly against a wall or easel to prevent tipping.
📋 Step-by-Step Guide (5 Steps)
Establish Base Generations and the Core Couple
Draw two horizontal generational reference lines across the top and middle of your board. In the middle tier, write 'You' in black marker on the left and 'Widow' on the right, connecting them with a double horizontal line to denote marriage. Note above the Widow that she has an adult 'Grown Daughter'.
- • 'You' and 'Widow' boxes drawn side-by-side connected by a double line
- • 'Grown Daughter' box positioned beside the Widow in the same generational tier
- • Placing the Grown Daughter in the child generation tier below instead of as an adult marriage peer
Chart the Father's Marriage to the Stepdaughter
Place 'Your Father' on the upper generational tier above 'You' connected by a vertical biological descent line. Draw an angled blue marriage line connecting 'Your Father' directly to the 'Grown Daughter'. Add a label indicating this makes your stepdaughter into your stepmother.
- • 'Your Father' positioned directly above 'You'
- • Blue marriage line connecting 'Your Father' to the 'Grown Daughter'
- • Drawing the father's marriage line directly to the Widow instead of her daughter
Add the First Child and Trace the Brother-in-Law Paradox
Draw a lower generational tier beneath 'You' and the 'Widow', adding 'Your Son'. Connect 'Your Son' with biological lines descending from your marriage. Draw a dotted green relationship line from 'Your Son' to 'Your Father', showing your son is your father's brother-in-law.
- • 'Your Son' box on the bottom tier below 'You' and 'Widow'
- • Dotted green line connecting 'Your Son' across to 'Your Father' with label 'Brother-in-law'
- • Connecting the son biologically to the Grown Daughter instead of the Widow
Chart the Second Child and Trace the Grandchild Uncle Paradox
Add a second child box labeled 'Father's Son' beneath the 'Your Father' and 'Grown Daughter' marriage. Connect biological lines down to this child, then draw a red line from 'Father's Son' to 'You', labeling him as both your brother and your grandchild.
- • 'Father's Son' box aligned on the lower tier below the Father-Daughter marriage
- • Red relationship line connecting 'Father's Son' to 'You' labeled 'Brother / Grandchild'
- • Forgetting to link the child to your wife's status as grandmother
Complete the Grandparent Loop and Final Deduction
Draw a thick red highlight line connecting 'Widow' to 'Your Father's Mother' role, establishing her as your grandmother. Conclude the final logical bridge by drawing a circular bracket around 'You' and labeling the summary at the bottom: 'Husband of Grandmother = Grandfather'.
- • Complete closed network showing all 4 adults and 2 children with distinct color-coded links
- • Bold final deduction box reading 'I Am My Own Grandpa' at the base of the board
- • Omitting the key bridge premise that marrying someone's grandmother makes you their grandfather
Credit: inspired by an original tutorial by BlobbyClips — watch the original on YouTube.
Don’t have everything?
- No Whiteboard or large poster board? Large sheet of butcher paper or taped printer paper sheets
- No 4 different colored dry-erase markers? Standard ballpoint pens with different hatch patterns (solid, dashed, dotted)