Table schema:
CREATE TABLE table_name_25 (northumberland_senior_benevolent_bowl VARCHAR, northumberland_minor_cup VARCHAR)

Question: Who won the Northumberland Senior Benevolent Bowl, when the Northumberland Minor Cup was won by Whitley Bay 'a'?
SQL: SELECT northumberland_senior_benevolent_bowl FROM table_name_25 WHERE northumberland_minor_cup = "whitley bay 'a'"