The affection is mainly biological factor. Then further sort of strengthening, that religion helps.
Dalai LamaโInterdependence is a fundamental law of nature. Even tiny insects survive by mutual cooperation based on innate recognition of their interconnectedness. It is because our own human existence is so dependent on the help of others that our need for love lies at the very foundation of our existence. Therefore we need a genuine sense of responsibility and a sincere concern for the welfare of others.
Dalai Lama