Riddle me this... UPDATE

Gabrielle

My dad’s oldest brother is biologically his brother and his cousin.... how?

I know the answer, just wondering if anyone else can guess it!

Also, share your own interesting family stories!!! I love to hear them!

UPDATE: answer! So my dad’s mom (my grandma) was married and had my dad’s older brother. Well her husband passed away and Then she married his brother (my grandpa) and then had 4 more kids with him! So interesting!