diff --git a/src/main/java/com/jcloisterzone/XMLUtils.java b/src/main/java/com/jcloisterzone/XMLUtils.java
index 39419499..9c757126 100644
--- a/src/main/java/com/jcloisterzone/XMLUtils.java
+++ b/src/main/java/com/jcloisterzone/XMLUtils.java
@@ -103,4 +103,15 @@ public static Integer attributeIntValue(Element e, String attr, Integer defaultV
         }
         return Integer.parseInt(e.getAttribute(attr));
     }
+
+    public static String attributeStringValue(Element e, String attr) {
+        return attributeStringValue(e, attr, null);
+    }
+
+    public static String attributeStringValue(Element e, String attr, String defaultValue) {
+        if (!e.hasAttribute(attr)) {
+            return defaultValue;
+        }
+        return e.getAttribute(attr);
+    }
 }
diff --git a/src/main/java/com/jcloisterzone/engine/Engine.java b/src/main/java/com/jcloisterzone/engine/Engine.java
index b706da3a..1e470a25 100644
--- a/src/main/java/com/jcloisterzone/engine/Engine.java
+++ b/src/main/java/com/jcloisterzone/engine/Engine.java
@@ -148,6 +148,7 @@ private GameSetup createSetupFromMessage(GameSetupMessage setupMsg) {
         capabilities = addCapabilities(capabilities, setupMsg,"watchtower", WatchtowerCapability.class);
 
         capabilities = addCapabilities(capabilities, setupMsg,"robbers-son", RobbersSonCapability.class);
+        capabilities = addCapabilities(capabilities, setupMsg,"families", FamiliesCapability.class);
 
         Map<Rule, Object> rules = HashMap.empty();
         if (setupMsg.getElements().containsKey("farmers")) {
diff --git a/src/main/java/com/jcloisterzone/feature/modifier/StringNonMergingModifier.java b/src/main/java/com/jcloisterzone/feature/modifier/StringNonMergingModifier.java
new file mode 100644
index 00000000..8528b268
--- /dev/null
+++ b/src/main/java/com/jcloisterzone/feature/modifier/StringNonMergingModifier.java
@@ -0,0 +1,24 @@
+package com.jcloisterzone.feature.modifier;
+
+import com.jcloisterzone.game.setup.SetupQuery;
+
+public class StringNonMergingModifier extends FeatureModifier<String> {
+
+    public StringNonMergingModifier(String selector, SetupQuery enabledBy) {
+        super(selector, enabledBy);
+    }
+
+    @Override
+    public String mergeValues(String a, String b) {
+    	if (a != null) {
+			return (b != null && a.equals(b)) ? a : null;
+    	} else {
+    		return (b != null) ? b : null;
+    	}
+    }
+
+    @Override
+    public String valueOf(String attr) {
+        return attr;
+    }
+}
diff --git a/src/main/java/com/jcloisterzone/game/capability/FamiliesCapability.java b/src/main/java/com/jcloisterzone/game/capability/FamiliesCapability.java
new file mode 100644
index 00000000..3c37069c
--- /dev/null
+++ b/src/main/java/com/jcloisterzone/game/capability/FamiliesCapability.java
@@ -0,0 +1,65 @@
+package com.jcloisterzone.game.capability;
+
+import com.jcloisterzone.board.*;
+import com.jcloisterzone.feature.City;
+import com.jcloisterzone.feature.Feature;
+import com.jcloisterzone.feature.Structure;
+import com.jcloisterzone.feature.modifier.StringNonMergingNonEmptyModifier;
+import com.jcloisterzone.game.Capability;
+import com.jcloisterzone.game.state.GameState;
+import com.jcloisterzone.game.state.PlacedTile;
+import com.jcloisterzone.reducers.PlaceTile;
+import io.vavr.collection.List;
+
+import static com.jcloisterzone.XMLUtils.attributeIntValue;
+import static com.jcloisterzone.XMLUtils.attributeStringValue;
+
+import org.w3c.dom.Element;
+
+public class FamiliesCapability extends Capability<PlacedTile> {
+
+	public static final StringNonMergingNonEmptyModifier FAMILY = new StringNonMergingNonEmptyModifier("family", null);
+
+	@Override
+    public Feature initFeature(GameState state, String tileId, Feature feature, Element xml) {
+        if (feature instanceof City) {
+        	if (attributeIntValue(xml, "pennants", 0) > 0 ) {
+        		String family = "blue";
+        		if (xml.hasAttribute("family")) {
+        			family = xml.getAttribute("family");
+        		}
+        		feature = ((City) feature).putModifier(FAMILY, family);
+        	}
+        }
+        return feature;
+    }
+
+	@Override
+    public boolean isTilePlacementAllowed(GameState state, Tile tile, PlacementOption placement) {
+        Position pos = placement.getPosition();
+        Rotation rot = placement.getRotation();
+
+        state = (new PlaceTile(tile, pos, rot)).apply(state);
+
+        List<City> cities = state.getTileFeatures2(pos, Structure.class)
+                .filter(fp -> City.class.isInstance(fp._2))
+        		.map(t -> (City) t._2)
+           		.toList();
+
+        if (cities.size()==0) {
+        	// No city
+        	return true;
+        }
+        
+        for(City city : cities) {
+        	if (city.getModifier(state, City.PENNANTS, 0) > 0) {
+        		if (city.getModifier(state, FAMILY, null).equals("")) {
+        			// Family is null, not allowed placement, because families joined due to StringNonMergingModifier = null
+        			return false;
+        		}
+        	}
+        }
+        
+        return true;
+    }
+}