public Block withRelationships(RelationshipsListItem... relationships) {
        if (this.relationships == null) {
            setRelationships(new java.util.ArrayList<RelationshipsListItem>(relationships.length));
        }
        for (RelationshipsListItem ele : relationships) {
            this.relationships.add(ele);
        }
        return this;
    }
<p>
A list of child blocks of the current block. For example, a LINE object has child blocks for each WORD block
that's part of the line of text.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setRelationships(java.util.Collection)} or {@link #withRelationships(java.util.Collection)} if you want
to override the existing values.
</p>

@param relationships
       A list of child blocks of the current block. For example, a LINE object has child blocks for each WORD
       block that's part of the line of text.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-comprehend/src/main/java/com/amazonaws/services/comprehend/model/Block.java