Answer by Suminda Sirinath S. Dharmasena for Are buddhists also called brothers and sisters?

Usually when speaking about someone who is following the buddha teach is called a monk.

This is not true. There are lay followers and ordinated followers and the latter are the monks through both follow Buddhism.

But are monks or other buddhists sometimes also called brothers and sisters?

Brothers is a Christian concept which is not found in Buddhism.

Is it common or very rare?

This is non existent.

And what is the reason behind it?

This is like asking why an apple does not have a peelable skin. There are 2 different institutions which developed independent of each other. So there is no sharing of such concepts.

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