create table AddTbl (
  FirstName TEXT,
  LastName TEXT,
  Birth INTEGER
);

create table ValTbl (
  LastName TEXT,
  District TEXT
);

insert into AddTbl values ('Jane', 'Doe', 1980); -- mother
insert into AddTbl values ('John', 'Doe', 1980); -- father
insert into AddTbl values ('John', 'Doe', 2005); -- son

insert into ValTbl values ('Doe', 'Somewhere');

select distinct a.FirstName, a.LastName, v.District
from AddTbl a 
  inner join ValTbl v
  on a.LastName = v.LastName
order by a.FirstName;

select '---';

select a.FirstName, a.LastName, v.District
from AddTbl a 
  inner join (select distinct LastName, District from ValTbl) v
  on a.LastName = v.LastName
order by Firstname;