For Finding All the ChildNodes you can use the below Snippet
List<WebElement> childs = MyCurrentWebElement.findElements(By.xpath("./child::*"));
for (WebElement e : childs)
{
System.out.println(e.getTagName());
}
Note that this will give all the Child Nodes at same level -> Like if you have structure like this :
<Html>
<body>
<div> ---suppose this is current WebElement
<a>
<a>
<img>
<a>
<img>
<a>
It will give me tag names of 3 anchor tags here only . If you want all the child Elements recursively , you can replace the above code with MyCurrentWebElement.findElements(By.xpath(".//*"));
Hope That Helps !!