Most of the times the "Relationship Finder" shows your relationships through your paternal line because that side of your tree is more complete and there are many more converging lines on that side than on your maternal line.
The relationship between you and Donald Pilkington (Pilkington-425) is:
Ruth LaMarr and Donald Pilkington are both descendants of Henry (Pilkington) Kingston.
1. Ruth is the daughter of Marilyn June (Good) LaMarr [unknown confidence]
2. Bonnie is the daughter of Zelpha Lorrayne (Pilkington) Mason [unknown confidence]
3. Zelpha is the daughter of Henry Matthew (Pilkington) Kingston [unknown confidence]
This makes Henry the great grandfather of Ruth.
1. Donald is the son of [private father] [unknown confidence]
2. [Private] is the son of Henry Matthew (Pilkington) Kingston [unknown confidence]
This makes Henry the grandfather of Donald.
This relationship is through your maternal line.
Once your maternal side had more ancestors and connections, the "Relationship Finder" will find more relationships on that line.