diff --git a/internal/domain/main-entities/patient/entity.go b/internal/domain/main-entities/patient/entity.go
index 83afa6ce..9ad63ce8 100644
--- a/internal/domain/main-entities/patient/entity.go
+++ b/internal/domain/main-entities/patient/entity.go
@@ -15,7 +15,14 @@ type Patient struct {
 	RegisteredAt           *time.Time           `json:"registeredAt"`
 	RegisteredBy_User_Name *string              `json:"registeredBy_user_name" gorm:"size:100"`
 	Status_Code            erc.ActiveStatusCode `json:"status_code" gorm:"not null;size:10"`
-	Number                 *string              `json:"number" gorm:"unique;size:15"`
-	Parent_Number          *string              `json:"parent_number"`
-	Parent                 *Patient             `json:"parent,omitempty" gorm:"foreignKey:Parent_Number;references:Number"`
+
+	// Normal UNIQUE index — required for the foreign key reference
+	Number *string `json:"number" gorm:"size:15;unique"`
+
+	// Partial unique index — keeps Number unique only for non–soft-deleted records.
+	// Allows duplicate Number values when previous records are soft-deleted.
+	_ struct{} `gorm:"uniqueIndex:idx_number_active,where:\"DeletedAt\" IS NULL"`
+
+	Parent_Number *string  `json:"parent_number"`
+	Parent        *Patient `json:"parent,omitempty" gorm:"foreignKey:Parent_Number;references:Number"`
 }