diff --git a/lib/src/form/src/controller.dart b/lib/src/form/src/controller.dart
index ae18f60..1dda67d 100644
--- a/lib/src/form/src/controller.dart
+++ b/lib/src/form/src/controller.dart
@@ -468,32 +468,63 @@ class AstromicFormController extends FormController {
     }
   }
 
-  bool validateGroup(String groupID, {Map<String, int>? parents}) {
+  (List<String> fields, List<String> values) _checkSubgroupsToValidate(String groupID, {Map<String, int>? parents}) {
+    FormGroupStructure? groupStructure = getGroupStructure(groupID);
+    String? prefix;
+    if (parents != null) {
+      prefix = parents.entries.map((MapEntry<String, int> parentEntry) => standeredGroupFormat(parentEntry.key, parentEntry.value.toString(), null)).join('-');
+    }
+    //
+    //
+    List<String> fieldsToValidate = <String>[];
+    List<String> valuesToValidate = <String>[];
+    for ((int, FormGroupStructure) sg in (groupStructure?.subGroups ?? <(int, FormGroupStructure)>[])) {
+      FormGroupStructure? subgroupStructure = getGroupStructure(sg.$2.id);
+      int sgInstances = getInstanceCount(sg.$2.id, parents: <String, int>{...?parents});
+      for (int i = 0; i < sgInstances; i++) {
+        _checkSubgroupsToValidate(
+          sg.$2.id,
+          parents: <String, int>{
+            ...?parents,
+            ...<String, int>{sg.$2.id: i}
+          },
+        );
+        for (String fieldID in subgroupStructure!.fields) {
+          fieldsToValidate.add(standeredGroupFormat((prefix != null ? '$prefix-' : '') + sg.$2.id, i.toString(), fieldID));
+        }
+        for (String valueID in (subgroupStructure.values ?? <String>[])) {
+          valuesToValidate.add(standeredGroupFormat((prefix != null ? '$prefix-' : '') + sg.$2.id, i.toString(), valueID));
+        }
+      }
+    }
+    return (fieldsToValidate, valuesToValidate);
+  }
+
+  /// Validate the group with ID.
+  bool validateGroup(String groupID) {
     // Get tha main targeted group's structure
     FormGroupStructure? groupStructure = getGroupStructure(groupID);
     assert(groupStructure != null, 'The Group $groupID doesn\'t seem to be found, are you sure you initialized it?');
 
-    // Get the prefix for subgroups if exists
-    String? prefix;
-    if (isASubGroup(groupID) && parents != null) {
-      prefix = parents.entries.map((MapEntry<String, int> parentEntry) => standeredGroupFormat(parentEntry.key, parentEntry.value.toString(), null)).join('-');
-    }
-
     // Get current instances of this group and the new index.
-    int currentGroupInstances = getInstanceCount(groupID, parents: parents);
+    int currentGroupInstances = getInstanceCount(groupID);
 
     List<String> fieldsToValidate = <String>[];
     List<String> valuesToValidate = <String>[];
+
     for (int i = 0; i < currentGroupInstances; i++) {
       for (String fieldID in groupStructure!.fields) {
-        fieldsToValidate.add((prefix != null ? '$prefix-' : '') + standeredGroupFormat(groupID, i.toString(), fieldID));
+        fieldsToValidate.add(standeredGroupFormat(groupID, i.toString(), fieldID));
       }
       for (String valueID in (groupStructure.values ?? <String>[])) {
-        valuesToValidate.add((prefix != null ? '$prefix-' : '') + standeredGroupFormat(groupID, i.toString(), valueID));
+        valuesToValidate.add(standeredGroupFormat(groupID, i.toString(), valueID));
       }
-    }
 
-    //
+      // Loop through the subgroups and get their fields and values
+      (List<String> fields, List<String> values) sgRet = _checkSubgroupsToValidate(groupID, parents: <String, int>{groupID: i});
+      fieldsToValidate.addAll(sgRet.$1);
+      valuesToValidate.addAll(sgRet.$2);
+    } //
     return validateOnly(fieldsToValidate) && validateValues(valuesToValidate);
   }
   //!SECTION