The chant that the three siblings say at the end of the phone conversation that is a reminder of the importance of their family relationship throughout their lives is an example of

Ritual

Explanation:

Ritual is a sequentially arranges set of activities, that include - words, actions, objects.

The chant that three siblings say at end phone conversation, reminding them of importance of family relationship throughout their lives : illustrates verbal action based sequential ending of their telephonic conversation.

So, it is a Ritual

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