diff --git a/docs/diagrams/StorageClassDiagram.puml b/docs/diagrams/StorageClassDiagram.puml
index 9c6b17a4ce7..89d15af0484 100644
--- a/docs/diagrams/StorageClassDiagram.puml
+++ b/docs/diagrams/StorageClassDiagram.puml
@@ -20,6 +20,7 @@ Class JsonAddressBookStorage
 Class JsonSerializableAddressBook
 Class JsonAdaptedPerson
 Class JsonAdaptedGroup
+class JsonAdaptedPersonGroupAttendance
 }
 
 }
@@ -38,6 +39,7 @@ JsonUserPrefsStorage .up.|> UserPrefsStorage
 JsonAddressBookStorage .up.|> AddressBookStorage
 JsonAddressBookStorage ..> JsonSerializableAddressBook
 JsonSerializableAddressBook --> "*" JsonAdaptedPerson
-JsonAdaptedPerson --> "*" JsonAdaptedGroup
+JsonSerializableAddressBook --> "*" JsonAdaptedGroup
+JsonAdaptedPerson --> "*" JsonAdaptedPersonGroupAttendance
 
 @enduml
diff --git a/docs/diagrams/UiClassDiagram.puml b/docs/diagrams/UiClassDiagram.puml
index 95473d5aa19..72773a87685 100644
--- a/docs/diagrams/UiClassDiagram.puml
+++ b/docs/diagrams/UiClassDiagram.puml
@@ -9,6 +9,7 @@ Class "<<interface>>\nUi" as Ui
 Class "{abstract}\nUiPart" as UiPart
 Class UiManager
 Class MainWindow
+Class MailWindow
 Class HelpWindow
 Class ResultDisplay
 Class PersonListPanel
@@ -34,6 +35,7 @@ MainWindow *-down->  "1" CommandBox
 MainWindow *-down-> "1" ResultDisplay
 MainWindow *-down-> "1" PersonListPanel
 MainWindow *-down-> "1" StatusBarFooter
+MainWindow --> "0..1" MailWindow
 MainWindow --> "0..1" HelpWindow
 
 PersonListPanel -down-> "*" PersonCard
@@ -45,6 +47,7 @@ CommandBox --|> UiPart
 PersonListPanel --|> UiPart
 PersonCard --|> UiPart
 StatusBarFooter --|> UiPart
+MailWindow --|> UiPart
 HelpWindow --|> UiPart
 
 PersonCard ..> Model
@@ -52,6 +55,7 @@ UiManager -right-> Logic
 MainWindow -left-> Logic
 
 PersonListPanel -[hidden]left- HelpWindow
+MailWindow -[hidden]left- CommandBox
 HelpWindow -[hidden]left- CommandBox
 CommandBox -[hidden]left- ResultDisplay
 ResultDisplay -[hidden]left- StatusBarFooter