diff --git a/lib/src/model/basic_event_with_sender.dart b/lib/src/model/basic_event_with_sender.dart
index 6c93fd07..6c90e8c9 100644
--- a/lib/src/model/basic_event_with_sender.dart
+++ b/lib/src/model/basic_event_with_sender.dart
@@ -28,10 +28,8 @@ class BasicEventWithSender extends BasicEvent {
 
   BasicEventWithSender();
 
-  BasicEventWithSender.fromJson(Map<String, dynamic> json) {
-    final basicEvent = BasicEvent.fromJson(json);
-    type = basicEvent.type;
-    content = basicEvent.content;
+  BasicEventWithSender.fromJson(Map<String, dynamic> json)
+      : super.fromJson(json) {
     senderId = json['sender'];
   }
 
diff --git a/lib/src/model/basic_room_event.dart b/lib/src/model/basic_room_event.dart
index 8a97ee72..27f28e8f 100644
--- a/lib/src/model/basic_room_event.dart
+++ b/lib/src/model/basic_room_event.dart
@@ -35,10 +35,7 @@ class BasicRoomEvent extends BasicEvent {
           type: type,
         );
 
-  BasicRoomEvent.fromJson(Map<String, dynamic> json) {
-    final basicEvent = BasicEvent.fromJson(json);
-    content = basicEvent.content;
-    type = basicEvent.type;
+  BasicRoomEvent.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
     roomId = json['room_id'];
   }
 
diff --git a/lib/src/model/filter.dart b/lib/src/model/filter.dart
index 7103ec1e..391537cf 100644
--- a/lib/src/model/filter.dart
+++ b/lib/src/model/filter.dart
@@ -190,14 +190,7 @@ class StateFilter extends EventFilter {
           notSenders: notSenders,
         );
 
-  StateFilter.fromJson(Map<String, dynamic> json) {
-    final eventFilter = EventFilter.fromJson(json);
-    limit = eventFilter.limit;
-    senders = eventFilter.senders;
-    types = eventFilter.types;
-    notRooms = eventFilter.notRooms;
-    notSenders = eventFilter.notSenders;
-
+  StateFilter.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
     notTypes = json['not_types']?.cast<String>();
     lazyLoadMembers = json['lazy_load_members'];
     includeRedundantMembers = json['include_redundant_members'];
diff --git a/lib/src/model/matrix_event.dart b/lib/src/model/matrix_event.dart
index 74dd4296..705f2f04 100644
--- a/lib/src/model/matrix_event.dart
+++ b/lib/src/model/matrix_event.dart
@@ -34,12 +34,7 @@ class MatrixEvent extends StrippedStateEvent {
 
   MatrixEvent();
 
-  MatrixEvent.fromJson(Map<String, dynamic> json) {
-    final strippedStateEvent = StrippedStateEvent.fromJson(json);
-    content = strippedStateEvent.content;
-    type = strippedStateEvent.type;
-    senderId = strippedStateEvent.senderId;
-    stateKey = strippedStateEvent.stateKey;
+  MatrixEvent.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
     eventId = json['event_id'];
     roomId = json['room_id'];
     originServerTs =
diff --git a/lib/src/model/presence.dart b/lib/src/model/presence.dart
index 93d17c9b..7d9fb753 100644
--- a/lib/src/model/presence.dart
+++ b/lib/src/model/presence.dart
@@ -27,11 +27,7 @@ import 'presence_content.dart';
 class Presence extends BasicEventWithSender {
   PresenceContent presence;
 
-  Presence.fromJson(Map<String, dynamic> json) {
-    final basicEvent = BasicEventWithSender.fromJson(json);
-    type = basicEvent.type;
-    content = basicEvent.content;
-    senderId = basicEvent.senderId;
+  Presence.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
     presence = PresenceContent.fromJson(content);
   }
 }
diff --git a/lib/src/model/stripped_state_event.dart b/lib/src/model/stripped_state_event.dart
index da9298ff..e6d1edd5 100644
--- a/lib/src/model/stripped_state_event.dart
+++ b/lib/src/model/stripped_state_event.dart
@@ -27,11 +27,8 @@ class StrippedStateEvent extends BasicEventWithSender {
   String stateKey;
 
   StrippedStateEvent();
-  StrippedStateEvent.fromJson(Map<String, dynamic> json) {
-    final basicEvent = BasicEventWithSender.fromJson(json);
-    content = basicEvent.content;
-    type = basicEvent.type;
-    senderId = basicEvent.senderId;
+  StrippedStateEvent.fromJson(Map<String, dynamic> json)
+      : super.fromJson(json) {
     stateKey = json['state_key'];
   }