SOLR Support for Parent Child relationship in DIH using XPathEntityProcessor

SOLR DIH seems to have added support for parent child relationship ( block join) in SQL entity processor , but same seems to be missing for xml entity processor. My scenario is like this : an offer price will vary for different date ranges. So i am trying to represent it as parent-child as given below :

                   <doc>
                        <name>somename</name>
                       <doc> 
                          <daterange> <daterange>
                          <price>7878</price>
                        </doc>
                       <doc> 
                          <daterange> <daterange>
                          <price>8182</price>
                        </doc>
                   </doc>

i can use /update REST for this, but the size of my index file will be around 1Gb so want to avoid it. Is there another way this can be implemented using DIH ?