diff --git a/MyTimeline.py b/MyTimeline.py
index 4a3ca3d..a194d0e 100644
--- a/MyTimeline.py
+++ b/MyTimeline.py
@@ -860,7 +860,7 @@ class MyTimelineView(NavigationView):
         category_event_types = {}  # Map category to list of event types
         
         # First pass: collect event types by category
-        for event_type_obj in EVENT_COLORS.keys():
+        for event_type_obj in EVENT_COLORS:
             if event_type_obj not in EVENT_CATEGORIES:
                 continue
             category = EVENT_CATEGORIES[event_type_obj]
@@ -869,7 +869,7 @@ class MyTimelineView(NavigationView):
             category_event_types[category].append(event_type_obj)
         
         # Second pass: create UI with category checkboxes
-        for category in sorted(category_event_types.keys()):
+        for category in sorted(category_event_types):
             event_types_in_category = category_event_types[category]
             
             # Create category checkbox with three-state support
@@ -1243,7 +1243,7 @@ class MyTimelineView(NavigationView):
                     add_person_checkbox(child_ref.ref, _('Child'))
                 
                 # Only add expander if there are members to show
-                if len(members_box.get_children()) > 0:
+                if members_box.get_children():
                     # Create family checkbox with three-state support
                     family_checkbox = Gtk.CheckButton(label=family_name)