jQuery导航-更改input parent-parent-parent-parent-sibling的输入

我目前正在寻找一些jQuery的建议，因为我认为我这样做是不正确的，即使我得到了我想要的结果。

我想把一个输入的值改成最近的输入的值，当它被改变的时候，一个类的。milestone。我想改变的输入是保持的输入我想让它等于修改后的输入。下面是我不能更改的HTML，因为这是一个产品。

<div class="container area  dform_section_area6">
    <div class="box  box13 two">
        <div class="dform_section_box13">
            <div style="clear: both;" data-type="html" data-name="business_case_approved_pmr" id="dform_widget_html_business_case_approved_pmr" data-active="true" class="dform_widget  dform_widget_type_html dform_widget_business_case_approved_pmr">
                <p>Business Case Approved</p>
            </div>
        </div>
    </div>
    <div class="box  box14 two">
        <div class="dform_section_box14">
            <div data-type="date" data-name="bc_approved_planned_pmr" data-active="true" data-agentonly="false" class="container dform_widget  dform_widget_field dform_widget_type_date dform_widget_bc_approved_planned_pmr dform_widget_bc_approved_planned_bc">
                <div>
                    <label for="dform_widget_bc_approved_planned_pmr">Planned</label>
                </div>
                <div>
                    <input id="dform_widget_bc_approved_planned_pmr" type="date" name="bc_approved_planned_pmr" data-mapfrom="bc_approved_planned_bc" class="dform_field_active">
                </div>
            </div>
        </div>
    </div>
    <div class="box  box15 two">
        <div class="dform_section_box15">
            <div data-type="select" data-name="bcapproval_on_target" data-active="true" data-agentonly="false" class="container dform_widget  dform_widget_field dform_widget_type_select dform_widget_bcapproval_on_target dform_widget_">
                <div>
                    <label for="dform_widget_bcapproval_on_target">On target?</label>
                </div>
                <div>
                    <select id="dform_widget_bcapproval_on_target" name="bcapproval_on_target" class="dform_field_active">
                        <option></option>
                        <option value="Yes" data-off="bc_approved_revised_pmr">Yes</option>
                        <option value="No" data-on="bc_approved_revised_pmr">No</option>
                    </select>
                </div>
            </div>
        </div>
    </div>
    <div class="box  box16 two">
        <div class="dform_section_box16">
            <div data-type="date" data-name="bc_approved_revised_pmr" data-active="false" data-agentonly="false" class="container dform_widget milestone mrevise dform_widget_field dform_widget_type_date dform_widget_bc_approved_revised_pmr dform_widget_">
                <div>
                    <label for="dform_widget_bc_approved_revised_pmr">*Revised</label>
                </div>
                <div>
                    <input id="dform_widget_bc_approved_revised_pmr" type="date" name="bc_approved_revised_pmr" class="">
                </div>
            </div>
        </div>
    </div>
    <div class="box  box17 two">
        <div class="dform_section_box17">
            <div data-type="date" data-name="gate_3_actual1" data-active="true" data-agentonly="false" class="container dform_widget  dform_widget_field dform_widget_type_date dform_widget_gate_3_actual1 dform_widget_">
                <div>
                    <label for="dform_widget_gate_3_actual1">Actual</label>
                </div>
                <div>
                    <input id="dform_widget_gate_3_actual1" type="date" name="gate_3_actual1" class="dform_field_active">
                </div>
            </div>
        </div>
    </div>
    <div class="box  box18 last two">
        <div class="dform_section_box18">
            <div data-type="date" data-name="bc_approved_planned_bc" data-active="true" data-agentonly="false" class="container dform_widget param mrevise dform_widget_field dform_widget_type_date dform_widget_bc_approved_planned_bc dform_widget_">
                <div>
                    <label for="dform_widget_bc_approved_planned_bc">holding</label>
                </div>
                <div>
                    <input id="dform_widget_bc_approved_planned_bc" type="date" name="bc_approved_planned_bc" class="dform_field_active">
                </div>
            </div>
        </div>
    </div>
</div>

我正在使用下面的jQuery来找到我想要更新的输入值，但我忍不住认为必须有一个不那么冗长的方式来改变这一点。我不能只引用输入的ID，因为我需要为20多个字段这样做。

$(this).parent().parent().parent().parent().next().next().find('.param').find('input').val()

This =

<input id="dform_widget_bc_approved_revised_pmr" type="date" name="bc_approved_revised_pmr" class="">