diff --git a/ast-generator/src/ast_node/mod.rs b/ast-generator/src/ast_node/mod.rs
index f09cf79..b6d5264 100644
--- a/ast-generator/src/ast_node/mod.rs
+++ b/ast-generator/src/ast_node/mod.rs
@@ -67,7 +67,7 @@ pub fn make_ast_enum_member(build_spec: &BuildSpec) -> Option<TokenStream> {
     }
         .map(|type_ident| {
             quote! {
-                #type_ident(#type_ident)
+                #type_ident(&'a #type_ident)
             }
         })
 }
\ No newline at end of file
diff --git a/ast-generator/src/ast_node/polymorphic_type_ast_node.rs b/ast-generator/src/ast_node/polymorphic_type_ast_node.rs
index 2df90ee..d698160 100644
--- a/ast-generator/src/ast_node/polymorphic_type_ast_node.rs
+++ b/ast-generator/src/ast_node/polymorphic_type_ast_node.rs
@@ -11,7 +11,7 @@ pub fn make_polymorphic_type_ast_node_impl(spec: &PolymorphicTypeBuildSpec) -> T
             let variant_ident = format_ident!("{}", variant.name());
             let child_ident = format_ident!("{}", variant.inner_kind().to_case(Case::Snake));
             quote! {
-                #type_ident::#variant_ident(#child_ident) => vec![#child_ident]
+                #type_ident::#variant_ident(#child_ident) => vec![#child_ident.as_node_ref()]
             }
         })
         .collect::<Vec<_>>();
diff --git a/ast-generator/src/ast_node/struct_ast_node.rs b/ast-generator/src/ast_node/struct_ast_node.rs
index 102874f..ff32739 100644
--- a/ast-generator/src/ast_node/struct_ast_node.rs
+++ b/ast-generator/src/ast_node/struct_ast_node.rs
@@ -8,41 +8,44 @@ pub fn make_struct_ast_node_impl(spec: &StructSpec) -> TokenStream {
         .children()
         .map(|child| match child {
             StructChild::SkipChild(_) => None,
-            StructChild::VecChild(vec_child) => {
-                match vec_child.build() {
-                    VecChildBuild::String(_) => None,
-                    VecChildBuild::Node(_) => {
-                        let child_ident = format_ident!("{}", vec_child.name());
-                        let children_stream = quote! {
-                            for child in self.#child_ident().map(AstNode::as_node_ref).collect() {
-                                children.push(child);
+            StructChild::VecChild(vec_child) => match vec_child.build() {
+                VecChildBuild::String(_) => None,
+                VecChildBuild::Node(_) => {
+                    let child_ident = format_ident!("{}", vec_child.name());
+                    let children_stream = quote! {
+                        for child in self.#child_ident().map(AstNode::as_node_ref) {
+                            children.push(child);
+                        }
+                    };
+                    Some(children_stream)
+                }
+            },
+            StructChild::MemberChild(member_child) => match member_child.build() {
+                MemberChildBuild::Node(node_child) => {
+                    let child_ident = format_ident!("{}", member_child.name());
+                    if member_child.optional() {
+                        Some(quote! {
+                            if let Some(#child_ident) = self.#child_ident() {
+                                children.push(#child_ident.as_node_ref());
                             }
-                        };
-                        Some(children_stream)
+                        })
+                    } else {
+                        Some(quote! {
+                            children.push(self.#child_ident().as_node_ref())
+                        })
                     }
                 }
-            }
-            StructChild::MemberChild(member_child) => {
-                match member_child.build() {
-                    MemberChildBuild::Node(_) => {
-                        let child_ident = format_ident!("{}", member_child.name());
-                        let child_stream = quote! {
-                            children.add(self.#child_ident().as_node_ref())
-                        };
-                        Some(child_stream)
-                    }
-                    MemberChildBuild::Boolean(_) => None
-                }
-            }
+                MemberChildBuild::Boolean(_) => None,
+            },
         })
         .filter(Option::is_some)
         .map(Option::unwrap)
         .collect::<Vec<_>>();
-    
+
     quote! {
         impl AstNode for #type_ident {
             fn children(&self) -> Vec<AstNodeRef> {
-                let children: Vec<AstNodeRef> = vec![];
+                let mut children: Vec<AstNodeRef> = vec![];
                 #(#child_adders;)*
                 children
             }
diff --git a/ast-generator/src/lib.rs b/ast-generator/src/lib.rs
index 2e11e1c..b013867 100644
--- a/ast-generator/src/lib.rs
+++ b/ast-generator/src/lib.rs
@@ -11,11 +11,11 @@ use crate::build_fn::make_build_fn;
 use crate::deserialize::deserialize_yaml_spec;
 use crate::pretty_print::make_pretty_print_impl;
 use crate::type_gen::make_type;
+use crate::walk::make_walk_fn;
 use proc_macro2::TokenStream;
 use quote::quote;
 use spec::BuildSpec;
 use syn::File;
-use crate::walk::make_walk_fn;
 
 fn debug_built_spec(build_spec: &BuildSpec, token_stream: &TokenStream) {
     println!("*** BuildSpec ***");
@@ -168,7 +168,7 @@ fn generate_ast_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
     let combined = quote! {
         use crate::ast::node::*;
 
-        pub enum AstNodeRef {
+        pub enum AstNodeRef<'a> {
             #(#ast_enum_members,)*
         }