Simplify family model and add Member.contact_email

- Replace the Guardianship through-model + self-referential M2M with a simple
  is_guardian flag on Member. Guardians in a family look after the family's
  dependents; guardians/dependents are now derived properties.
- Add Member.contact_email: own contact email, falling back to the linked
  user's login email, so a linked member need not store their email twice.
- Update admin (is_guardian in list/filter/inline; drop guardianship inline).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

accounts/admin.py

@@ -2,7 +2,7 @@ from django.contrib import admin
 from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
 
 from .forms import UserChangeForm, UserCreationForm
-from .models import Family, Guardianship, Member, User
+from .models import Family, Member, User
 
 
 @admin.register(User)
@@ -29,29 +29,19 @@ class UserAdmin(BaseUserAdmin):
     )
 
 
-class GuardianshipInline(admin.TabularInline):
-    """Guardians of a member (edit from the child's page)."""
-
-    model = Guardianship
-    fk_name = "child"
-    extra = 0
-    autocomplete_fields = ("guardian",)
-
-
 class MemberInline(admin.TabularInline):
     model = Member
     extra = 0
-    fields = ("first_name", "last_name", "date_of_birth", "license_number")
+    fields = ("first_name", "last_name", "date_of_birth", "is_guardian", "license_number")
     show_change_link = True
 
 
 @admin.register(Member)
 class MemberAdmin(admin.ModelAdmin):
-    list_display = ("last_name", "first_name", "date_of_birth", "license_number", "family", "user")
+    list_display = ("last_name", "first_name", "date_of_birth", "is_guardian", "license_number", "family", "user")
-    list_filter = ("family",)
+    list_filter = ("is_guardian", "family")
     search_fields = ("first_name", "last_name", "email", "license_number")
     autocomplete_fields = ("user", "family")
-    inlines = (GuardianshipInline,)
 
 
 @admin.register(Family)

accounts/migrations/0001_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 6.0.6 on 2026-07-01 22:04
+# Generated by Django 6.0.6 on 2026-07-01 22:16
 
 import accounts.managers
 import django.db.models.deletion
@@ -29,13 +29,6 @@ class Migration(migrations.Migration):
                 'ordering': ['name'],
             },
         ),
-        migrations.CreateModel(
-            name='Guardianship',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('relationship', models.CharField(choices=[('parent', 'Parent'), ('guardian', 'Guardian'), ('other', 'Other')], default='parent', max_length=20)),
-            ],
-        ),
         migrations.CreateModel(
             name='User',
             fields=[
@@ -68,30 +61,12 @@ class Migration(migrations.Migration):
                 ('emergency_phone', phonenumber_field.modelfields.PhoneNumberField(blank=True, max_length=128, region=None)),
                 ('license_number', models.CharField(blank=True, max_length=50)),
                 ('date_of_birth', models.DateField()),
+                ('is_guardian', models.BooleanField(default=False, help_text='Whether this member is a parent/guardian in their family.')),
                 ('family', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='members', to='accounts.family')),
-                ('guardians', models.ManyToManyField(related_name='dependents', through='accounts.Guardianship', through_fields=('child', 'guardian'), to='accounts.member')),
                 ('user', models.OneToOneField(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='member', to=settings.AUTH_USER_MODEL)),
             ],
             options={
                 'ordering': ['last_name', 'first_name'],
             },
         ),
-        migrations.AddField(
-            model_name='guardianship',
-            name='child',
-            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='child_links', to='accounts.member'),
-        ),
-        migrations.AddField(
-            model_name='guardianship',
-            name='guardian',
-            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='guardian_links', to='accounts.member'),
-        ),
-        migrations.AddConstraint(
-            model_name='guardianship',
-            constraint=models.UniqueConstraint(fields=('guardian', 'child'), name='unique_guardianship'),
-        ),
-        migrations.AddConstraint(
-            model_name='guardianship',
-            constraint=models.CheckConstraint(condition=models.Q(('guardian', models.F('child')), _negated=True), name='guardian_not_self'),
-        ),
     ]

accounts/models.py

@@ -59,7 +59,12 @@ class Family(models.Model):
 
 
 class Member(models.Model):
-    """A person in the club. May or may not have a login (:attr:`user`)."""
+    """A person in the club. May or may not have a login (:attr:`user`).
+
+    Family relationships are modelled by membership in a :class:`Family`:
+    guardians (``is_guardian=True``) look after the other members of the same
+    family (the dependents).
+    """
 
     user = models.OneToOneField(
         settings.AUTH_USER_MODEL,
@@ -72,6 +77,7 @@ class Member(models.Model):
     first_name = models.CharField(max_length=150)
     last_name = models.CharField(max_length=150)
     # Contact email — optional. Children may have none; a login email lives on User.
+    # Use `contact_email` to read it with a fallback to the linked user's login email.
     email = models.EmailField(blank=True)
     phone = PhoneNumberField(blank=True)
     emergency_phone = PhoneNumberField(blank=True)
@@ -85,12 +91,9 @@ class Member(models.Model):
         blank=True,
         related_name="members",
     )
-    guardians = models.ManyToManyField(
+    is_guardian = models.BooleanField(
-        "self",
+        default=False,
-        through="Guardianship",
+        help_text="Whether this member is a parent/guardian in their family.",
-        through_fields=("child", "guardian"),
-        symmetrical=False,
-        related_name="dependents",
     )
 
     class Meta:
@@ -99,42 +102,21 @@ class Member(models.Model):
     def __str__(self):
         return f"{self.first_name} {self.last_name}"
 
+    @property
+    def contact_email(self):
+        """Best email to reach this member: own contact email, else login email."""
+        return self.email or (self.user.email if self.user_id else "")
 
-class Guardianship(models.Model):
+    @property
-    """Directional guardian -> child relationship between two members."""
+    def guardians(self):
+        """Members of my family who look after me (only if I'm a dependent)."""
+        if self.is_guardian or self.family_id is None:
+            return Member.objects.none()
+        return self.family.members.filter(is_guardian=True)
 
-    class Relationship(models.TextChoices):
+    @property
-        PARENT = "parent", "Parent"
+    def dependents(self):
-        GUARDIAN = "guardian", "Guardian"
+        """Members of my family I look after (only if I'm a guardian)."""
-        OTHER = "other", "Other"
+        if not self.is_guardian or self.family_id is None:
-
+            return Member.objects.none()
-    guardian = models.ForeignKey(
+        return self.family.members.filter(is_guardian=False)
-        Member,
-        on_delete=models.CASCADE,
-        related_name="guardian_links",
-    )
-    child = models.ForeignKey(
-        Member,
-        on_delete=models.CASCADE,
-        related_name="child_links",
-    )
-    relationship = models.CharField(
-        max_length=20,
-        choices=Relationship.choices,
-        default=Relationship.PARENT,
-    )
-
-    class Meta:
-        constraints = [
-            models.UniqueConstraint(
-                fields=["guardian", "child"],
-                name="unique_guardianship",
-            ),
-            models.CheckConstraint(
-                condition=~models.Q(guardian=models.F("child")),
-                name="guardian_not_self",
-            ),
-        ]
-
-    def __str__(self):
-        return f"{self.guardian} → {self.child} ({self.get_relationship_display()})"

accounts/tests.py

@@ -1,8 +1,7 @@
 from django.core.exceptions import ValidationError
-from django.db import IntegrityError, transaction
 from django.test import TestCase
 
-from .models import Family, Guardianship, Member, User
+from .models import Family, Member, User
 
 
 class UserManagerTests(TestCase):
@@ -58,30 +57,53 @@ class MemberTests(TestCase):
         with self.assertRaises(ValidationError):
             member.full_clean()
 
+    def test_contact_email_prefers_own_then_login(self):
+        # No own email, no user -> empty.
+        member = Member.objects.create(
+            first_name="Kid", last_name="Smith", date_of_birth="2015-05-01"
+        )
+        self.assertEqual(member.contact_email, "")
 
-class FamilyAndGuardianshipTests(TestCase):
+        # Linked user, no own email -> falls back to login email.
+        member.user = User.objects.create_user(email="login@example.com", password="pw")
+        member.save()
+        self.assertEqual(member.contact_email, "login@example.com")
+
+        # Own contact email wins over login email.
+        member.email = "contact@example.com"
+        self.assertEqual(member.contact_email, "contact@example.com")
+
+
+class FamilyTests(TestCase):
     def setUp(self):
         self.family = Family.objects.create(name="The Smiths")
         self.parent = Member.objects.create(
-            first_name="Ann", last_name="Smith", date_of_birth="1980-01-01", family=self.family
+            first_name="Ann", last_name="Smith", date_of_birth="1980-01-01",
+            family=self.family, is_guardian=True,
         )
         self.child = Member.objects.create(
-            first_name="Kid", last_name="Smith", date_of_birth="2015-05-01", family=self.family
+            first_name="Kid", last_name="Smith", date_of_birth="2015-05-01",
+            family=self.family, is_guardian=False,
         )
 
     def test_family_groups_members(self):
         self.assertEqual(self.family.members.count(), 2)
 
-    def test_guardianship_relations_resolve(self):
+    def test_child_guardians_are_family_guardians(self):
-        Guardianship.objects.create(guardian=self.parent, child=self.child)
+        self.assertIn(self.parent, self.child.guardians)
-        self.assertIn(self.parent, self.child.guardians.all())
+        self.assertNotIn(self.child, self.child.guardians)
-        self.assertIn(self.child, self.parent.dependents.all())
 
-    def test_no_self_guardianship(self):
+    def test_guardian_dependents_are_family_non_guardians(self):
-        with transaction.atomic(), self.assertRaises(IntegrityError):
+        self.assertIn(self.child, self.parent.dependents)
-            Guardianship.objects.create(guardian=self.parent, child=self.parent)
+        self.assertNotIn(self.parent, self.parent.dependents)
 
-    def test_guardianship_is_unique(self):
+    def test_guardian_has_no_guardians_and_child_has_no_dependents(self):
-        Guardianship.objects.create(guardian=self.parent, child=self.child)
+        self.assertEqual(list(self.parent.guardians), [])
-        with transaction.atomic(), self.assertRaises(IntegrityError):
+        self.assertEqual(list(self.child.dependents), [])
-            Guardianship.objects.create(guardian=self.parent, child=self.child)
+
+    def test_member_without_family_has_no_relations(self):
+        loner = Member.objects.create(
+            first_name="Solo", last_name="Jones", date_of_birth="1990-01-01"
+        )
+        self.assertEqual(list(loner.guardians), [])
+        self.assertEqual(list(loner.dependents), [])