Bessie’s son is Gerald. Bessie’s sister is Jessie. Jessie’s great-granddaughter is Mary.
What is the relationship between Gerald and Mary?
TIA
Mary’s grandmother is Gerald’s cousin.
Mary’s mother is Gerald’s cousin, once removed.
So that makes Mary Gerald’s cousin, twice removed.
(I learned this on SDMB, by the way. 
)
Gerald’s grandson and Mary are third cousins, if my math is right.
[del]Jessie’s[/del] Mary’s great-great-grandparent is Gerald’s grandparent, so they are first cousins twice removed.
The removal indicates a generational difference.
First Cousins (sharing the same grandparents) are on the same generation. Your first cousin’s kid is your first cousin once removed because there is one generation difference.
Your kid and your first cousin’s kid are second cousins (no removals–same generation).
Your grandchild and your first cousin’s grandchild are third cousins, etc.
You and your first cousin’s grandchild are first cousins twice removed…two generations different.
If you look at a family tree where there is horizontal alignment of the generations, it makes it a lot easier to figure the removals.
Mary is Gerald’s first cousin, twice removed downwards.
[Dark Helmet] Absolutely nothing. Which is what you are about to become.