如何用jquery选择父节点下的第一代子节点
<div id="dd0" class="clip" style="display:block;"><div class="dTreeNode" "><div class="dTreeNode" "><div class="dTreeNode" "><div class="dTreeNode" "><div class="dTreeNode" "><div class="dTreeNode" <div class="dTreeNode"> <div class="dTreeNode"> <div class="dTreeNode"><--这三个不想取到--></div><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode"><div class="dTreeNode">