CREATE TABLE Family (
  Id INT NOT NULL PRIMARY KEY,
  MotherId INT REFERENCES Family(Id),
  FatherId INT REFERENCES Family(Id),
  Name VARCHAR(30) NOT NULL,
  Age INT NOT NULL
);

INSERT INTO people(Id, MotherId, FatherId, Name, Age) VALUES(1, NULL, NULL, 'David', 65);
INSERT INTO people(Id, MotherId, FatherId, Name, Age) VALUES(2, NULL, NULL, 'Keti', 55);
INSERT INTO people(Id, MotherId, FatherId, Name, Age) VALUES(3, 2, 1, 'Crysti', 25);
INSERT INTO people(Id, MotherId, FatherId, Name, Age) VALUES(4, 2, 1, 'Ellen', 18);

Name      Age
=============
David    25
Keti      25