Html Agility Pack NextSibling

var htmlDoc = new HtmlDocument();
htmlDoc.LoadHtml(html);

var node = htmlDoc.DocumentNode.SelectSingleNode("//body/h1");

HtmlNode sibling = node.NextSibling;

while (sibling != null)
{
    if(sibling.NodeType == HtmlNodeType.Element)
        Console.WriteLine(sibling.OuterHtml);

    sibling = sibling.NextSibling;
}