I have a list of document types called newsItems I'm trying to display in a macro partial. They have a relatedLinks data type. I'm trying to display a simple list of the related links for each of the newsItems queried. I have successfully done this using similar code in previous versions of Umbraco but for some reason it's not working in a new site I'm developing using 7.6.

@inherits Umbraco.Web.Macros.PartialViewMacroPage

@{
    var query = CurrentPage.AncestorOrSelf(1).DescendantsOrSelf().Where("Visible && DocumentTypeAlias == @0", "newsItem").OrderBy("sortOrder desc");

    foreach (var page in query)
    {
        <h1>@page.Headline</h1>
        <p>@page.body</p>


        if (page.HasValue("relatedLinks") && page.relatedLinks.ToString().Length > 2)
        {
            foreach (var item in page.relatedLinks)
            {
                var linkUrl = (bool)item.isInternal ? Umbraco.NiceUrl(item.Value<int>("internal")) : item.link;
                var linkTarget = (bool)item.newWindow ? "_blank" : null;
                <p><a href="@linkUrl" target="@linkTarget">@item.caption</a></p>
            }
        }
    }
}

This line is trowing the error 'Umbraco.Web.Models.RelatedLink' does not contain a definition for 'isInternal'

var linkUrl = (bool)item.isInternal ? Umbraco.NiceUrl(item.Value<int>("internal")) : item.link;

If I take out the contitional and just do var linkUrl = item.link it says it doesn't containg a definition for 'link'

Have I overlooked something? or is there a different recommended method of doing something in 7.6?