Let the table members contain members data and the table relations contain member relations data. relations.member_id will be a reference to the member, relations.related_member_id - to the related member. relations.type is enumerable relation type.
CREATE TABLE `members` (
`id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`name` TEXT NOT NULL ,
`details` TEXT NOT NULL
) ENGINE = INNODB;
CREATE TABLE `relations` (
`id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`member_id` INT NOT NULL ,
`related_member_id` INT NOT NULL ,
`type` ENUM( 'Child', 'Parent', 'Friend', 'Spouse' ) NOT NULL,
FOREIGN KEY (member_id) REFERENCES members(id),
FOREIGN KEY (related_member_id) REFERENCES members(id)
) ENGINE = INNODB;
UPD: MyISAM version (removed foreign keys, all possible foreign keys functionality should be handled by server side scripts):
CREATE TABLE `members` (
`id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`name` TEXT NOT NULL ,
`details` TEXT NOT NULL
) ENGINE = MyISAM;
CREATE TABLE `relations` (
`id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`member_id` INT NOT NULL ,
`related_member_id` INT NOT NULL ,
`type` ENUM( 'Child', 'Parent', 'Friend', 'Spouse' ) NOT NULL
) ENGINE = MyISAM;
