diff --git a/gramps/gen/filters/rules/person/_isrelatedwith.py b/gramps/gen/filters/rules/person/_isrelatedwith.py
index 2debae3c3..1ace5c2ac 100644
--- a/gramps/gen/filters/rules/person/_isrelatedwith.py
+++ b/gramps/gen/filters/rules/person/_isrelatedwith.py
@@ -63,34 +63,42 @@ class IsRelatedWith(Rule):
         return person.handle in self.relatives
 
 
-    def add_relative(self, person):
-        """Recursive function that scans relatives and add them to self.relatives"""
-        if not(person) or person.handle in self.relatives:
+    def add_relative(self, start):
+        """Non-recursive function that scans relatives and add them to self.relatives"""
+        if not(start):
             return
 
-        # Add the relative to the list
-        self.relatives.append(person.handle)
+        expand = [start]
+        relatives = {}
+
+        while expand:
+            person = expand.pop()
+            # Add the relative to the list
+            if person is None or (person.handle in relatives):
+                continue
+            relatives[person.handle] = True
         
-        for family_handle in person.get_parent_family_handle_list():
-            family = self.db.get_family_from_handle(family_handle)
-            if family:
-        # Check Parents
-                for parent_handle in (family.get_father_handle(), family.get_mother_handle()):
-                    if parent_handle:
-                        self.add_relative(self.db.get_person_from_handle(parent_handle))
-        # Check Sibilings
-                for child_ref in family.get_child_ref_list():
-                    self.add_relative(self.db.get_person_from_handle(child_ref.ref))
-
-        for family_handle in person.get_family_handle_list():
-            family = self.db.get_family_from_handle(family_handle)
-            if family:
-        # Check Spouse
-                for parent_handle in (family.get_father_handle(), family.get_mother_handle()):
-                    if parent_handle:
-                        self.add_relative(self.db.get_person_from_handle(parent_handle))
-        # Check Children
-                for child_ref in family.get_child_ref_list():
-                    self.add_relative(self.db.get_person_from_handle(child_ref.ref))
-
-        return
+            for family_handle in person.get_parent_family_handle_list():
+                family = self.db.get_family_from_handle(family_handle)
+                if family:
+            # Check Parents
+                    for parent_handle in (family.get_father_handle(), family.get_mother_handle()):
+                        if parent_handle:
+                            expand.append(self.db.get_person_from_handle(parent_handle))
+            # Check Sibilings
+                    for child_ref in family.get_child_ref_list():
+                        expand.append(self.db.get_person_from_handle(child_ref.ref))
+    
+            for family_handle in person.get_family_handle_list():
+                family = self.db.get_family_from_handle(family_handle)
+                if family:
+            # Check Spouse
+                    for parent_handle in (family.get_father_handle(), family.get_mother_handle()):
+                        if parent_handle:
+                            expand.append(self.db.get_person_from_handle(parent_handle))
+            # Check Children
+                    for child_ref in family.get_child_ref_list():
+                        expand.append(self.db.get_person_from_handle(child_ref.ref))
+    
+        self.relatives = list(relatives.keys())
+        return