diff --git a/rdt_visitor.go b/rdt_visitor.go
index c4d44d6..a707baa 100644
--- a/rdt_visitor.go
+++ b/rdt_visitor.go
@@ -44,15 +44,16 @@ func (visitor *RdtVisitor) Visit(tree antlr.ParseTree, target *UnknownShape) (Sh
 	return nil, fmt.Errorf("unknown node type %T", tree)
 }
 
-func (visitor *RdtVisitor) VisitChildren(node antlr.RuleNode, target *UnknownShape) ([]*BaseShape, error) {
+func (visitor *RdtVisitor) VisitUnionMembers(node antlr.RuleNode, target *UnknownShape) ([]*BaseShape, error) {
 	var shapes []*BaseShape
-	for _, n := range node.GetChildren() {
-		// Skip terminal nodes
-		if _, ok := n.(*antlr.TerminalNodeImpl); ok {
-			continue
-		}
+	children := node.GetChildren()
+	// Each union member is paired with a pipe separator so we increment by 2.
+	// type1 | type2 | type3
+	// ^     ^ ^     ^ ^
+	// 0     1 2     3 4
+	for i := 0; i < len(children); i += 2 {
 		baseResolved, implicitAnonShape, _ := visitor.raml.MakeNewShape("", "", target.Location, &target.Position)
-		s, err := visitor.Visit(n.(antlr.ParseTree), implicitAnonShape.(*UnknownShape))
+		s, err := visitor.Visit(children[i].(antlr.ParseTree), implicitAnonShape.(*UnknownShape))
 		if err != nil {
 			return nil, fmt.Errorf("visit children: %w", err)
 		}
@@ -130,7 +131,7 @@ func (visitor *RdtVisitor) VisitArray(ctx *rdt.ArrayContext, target *UnknownShap
 }
 
 func (visitor *RdtVisitor) VisitUnion(ctx *rdt.UnionContext, target *UnknownShape) (Shape, error) {
-	ss, err := visitor.VisitChildren(ctx, target)
+	ss, err := visitor.VisitUnionMembers(ctx, target)
 	if err != nil {
 		return nil, fmt.Errorf("visit children: %w", err)
 	}