diff --git a/src/AbstractActiveRecord.php b/src/AbstractActiveRecord.php
index b89801457..eb3db8185 100644
--- a/src/AbstractActiveRecord.php
+++ b/src/AbstractActiveRecord.php
@@ -339,7 +339,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
         $viaClass = null;
         $viaTable = null;
         $relation = $this->relationQuery($name);
-        $via = $relation?->getVia();
+        $via = $relation->getVia();
 
         if ($via !== null) {
             if ($this->getIsNewRecord() || $arClass->getIsNewRecord()) {
@@ -355,9 +355,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
                 // unset $viaName so that it can be reloaded to reflect the change.
                 /** @psalm-var string $viaName */
                 unset($this->related[$viaName]);
-            }
-
-            if ($via instanceof ActiveQueryInterface) {
+            } else {
                 $viaRelation = $via;
                 $from = $via->getFrom();
                 /** @psalm-var string $viaTable */
@@ -366,8 +364,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
 
             $columns = [];
 
-            /** @psalm-var ActiveQueryInterface|null $viaRelation */
-            $viaLink = $viaRelation?->getLink() ?? [];
+            $viaLink = $viaRelation->getLink();
 
             /**
              * @psalm-var string $a
@@ -378,7 +375,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
                 $columns[$a] = $this->$b;
             }
 
-            $link = $relation?->getLink() ?? [];
+            $link = $relation->getLink();
 
             /**
              * @psalm-var string $a
@@ -398,7 +395,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
                 $columns[$k] = $v;
             }
 
-            if ($viaClass instanceof ActiveRecordInterface && is_array($via)) {
+            if ($viaClass instanceof ActiveRecordInterface) {
                 /**
                  * @psalm-var string $column
                  * @psalm-var mixed $value
@@ -411,7 +408,7 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
             } elseif (is_string($viaTable)) {
                 $this->db->createCommand()->insert($viaTable, $columns)->execute();
             }
-        } elseif ($relation instanceof ActiveQueryInterface) {
+        } else {
             $link = $relation->getLink();
             $p1 = $arClass->isPrimaryKey(array_keys($link));
             $p2 = $this->isPrimaryKey(array_values($link));
@@ -438,13 +435,13 @@ public function link(string $name, ActiveRecordInterface $arClass, array $extraC
         }
 
         // update lazily loaded related objects
-        if ($relation instanceof ActiveRecordInterface && !$relation->getMultiple()) {
+        if (!$relation->getMultiple()) {
             $this->related[$name] = $arClass;
         } elseif (isset($this->related[$name])) {
-            $indexBy = $relation?->getIndexBy();
+            $indexBy = $relation->getIndexBy();
             if ($indexBy !== null) {
                 if ($indexBy instanceof Closure) {
-                    $index = $relation?->indexBy($arClass::class);
+                    $index = $relation->$indexBy($arClass::class);
                 } else {
                     $index = $arClass->$indexBy;
                 }
@@ -549,12 +546,8 @@ public function relation(string $name): ActiveRecordInterface|array|null
         return $this->retrieveRelation($name);
     }
 
-    public function relationQuery(string $name, bool $throwException = true): ActiveQueryInterface|null
+    public function relationQuery(string $name): ActiveQueryInterface
     {
-        if (!$throwException) {
-            return null;
-        }
-
         throw new InvalidArgumentException(static::class . ' has no relation named "' . $name . '".');
     }
 
@@ -811,7 +804,7 @@ public function unlink(string $name, ActiveRecordInterface $arClass, bool $delet
         $viaClass = null;
         $viaTable = null;
         $relation = $this->relationQuery($name);
-        $viaRelation = $relation?->getVia();
+        $viaRelation = $relation->getVia();
 
         if ($viaRelation !== null) {
             if (is_array($viaRelation)) {
@@ -835,7 +828,7 @@ public function unlink(string $name, ActiveRecordInterface $arClass, bool $delet
                     $columns[$a] = $this->$b;
                 }
 
-                $link = $relation?->getLink() ?? [];
+                $link = $relation->getLink();
 
                 foreach ($link as $a => $b) {
                     /** @psalm-var mixed */
@@ -893,7 +886,7 @@ public function unlink(string $name, ActiveRecordInterface $arClass, bool $delet
             }
         }
 
-        if ($relation instanceof ActiveQueryInterface && !$relation->getMultiple()) {
+        if (!$relation->getMultiple()) {
             unset($this->related[$name]);
         } elseif (isset($this->related[$name]) && is_array($this->related[$name])) {
             /** @psalm-var array<array-key, ActiveRecordInterface> $related */
@@ -928,9 +921,9 @@ public function unlinkAll(string $name, bool $delete = false): void
         $viaClass = null;
         $viaTable = null;
         $relation = $this->relationQuery($name);
-        $viaRelation = $relation?->getVia();
+        $viaRelation = $relation->getVia();
 
-        if ($relation instanceof ActiveQueryInterface && $viaRelation !== null) {
+        if ($viaRelation !== null) {
             if (is_array($viaRelation)) {
                 [$viaName, $viaRelation] = $viaRelation;
                 /** @psalm-var ActiveQueryInterface $viaRelation */
@@ -976,7 +969,7 @@ public function unlinkAll(string $name, bool $delete = false): void
                     $command->update($viaTable, $nulls, $condition)->execute();
                 }
             }
-        } elseif ($relation instanceof ActiveQueryInterface) {
+        } else {
             $relatedModel = $relation->getARInstance();
 
             $link = $relation->getLink();
diff --git a/src/ActiveRecordInterface.php b/src/ActiveRecordInterface.php
index f72a3c70d..4dfafaddd 100644
--- a/src/ActiveRecordInterface.php
+++ b/src/ActiveRecordInterface.php
@@ -326,7 +326,7 @@ public function relation(string $name): self|array|null;
      * Relations can be defined using {@see hasOne()} and {@see hasMany()} methods. For example:
      *
      * ```php
-     * public function relationQuery(string $name, bool $throwException = true): ActiveQueryInterface
+     * public function relationQuery(string $name): ActiveQueryInterface
      * {
      *     return match ($name) {
      *         'orders' => $this->hasMany(Order::class, ['customer_id' => 'id']),
@@ -337,13 +337,12 @@ public function relation(string $name): self|array|null;
      * ```
      *
      * @param string $name The relation name, for example `orders` (case-sensitive).
-     * @param bool $throwException Whether to throw exception if the relation doesn't exist.
      *
      * @throws InvalidArgumentException
      *
-     * @return ActiveQueryInterface|null The relational query object.
+     * @return ActiveQueryInterface The relational query object.
      */
-    public function relationQuery(string $name, bool $throwException = true): ActiveQueryInterface|null;
+    public function relationQuery(string $name): ActiveQueryInterface;
 
     /**
      * Resets relation data for the specified name.
diff --git a/src/Trait/MagicRelationsTrait.php b/src/Trait/MagicRelationsTrait.php
index c66c48bbe..86ae03247 100644
--- a/src/Trait/MagicRelationsTrait.php
+++ b/src/Trait/MagicRelationsTrait.php
@@ -37,25 +37,14 @@ trait MagicRelationsTrait
      * }
      * ```
      *
-     * @param string $name The relation name, for example `orders` for a relation defined via `getOrdersQuery()` method
-     * (case-sensitive).
-     * @param bool $throwException whether to throw exception if the relation does not exist.
-     *
      * @throws InvalidArgumentException if the named relation does not exist.
      * @throws ReflectionException
-     *
-     * @return ActiveQueryInterface|null the relational query object. If the relation does not exist and
-     * `$throwException` is `false`, `null` will be returned.
      */
-    public function relationQuery(string $name, bool $throwException = true): ActiveQueryInterface|null
+    public function relationQuery(string $name): ActiveQueryInterface
     {
         $getter = 'get' . ucfirst($name) . 'Query';
 
         if (!method_exists($this, $getter)) {
-            if (!$throwException) {
-                return null;
-            }
-
             throw new InvalidArgumentException(static::class . ' has no relation named "' . $name . '".');
         }
 
@@ -66,10 +55,6 @@ public function relationQuery(string $name, bool $throwException = true): Active
             $type === null
             || !is_a('\\' . $type->getName(), ActiveQueryInterface::class, true)
         ) {
-            if (!$throwException) {
-                return null;
-            }
-
             $typeName = $type === null ? 'mixed' : $type->getName();
 
             throw new InvalidArgumentException(
@@ -82,10 +67,6 @@ public function relationQuery(string $name, bool $throwException = true): Active
         $realName = lcfirst(substr($method->getName(), 3, -5));
 
         if ($realName !== $name) {
-            if (!$throwException) {
-                return null;
-            }
-
             throw new InvalidArgumentException(
                 'Relation names are case sensitive. ' . static::class
                 . " has a relation named \"$realName\" instead of \"$name\"."
diff --git a/tests/ActiveQueryTest.php b/tests/ActiveQueryTest.php
index 45417205a..73469fd46 100644
--- a/tests/ActiveQueryTest.php
+++ b/tests/ActiveQueryTest.php
@@ -2331,9 +2331,6 @@ public function testGetRelationInvalidArgumentException(): void
 
         $query = $customer->findOne(1);
 
-        /** Without throwing exception */
-        $this->assertEmpty($query->relationQuery('items', false));
-
         /** Throwing exception */
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage(
@@ -2350,9 +2347,6 @@ public function testGetRelationInvalidArgumentExceptionHasNoRelationNamed(): voi
 
         $query = $customer->findOne(1);
 
-        /** Without throwing exception */
-        $this->assertEmpty($query->relationQuery('item', false));
-
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage(
             'Relation query method "Yiisoft\ActiveRecord\Tests\Stubs\ActiveRecord\Customer::getItemQuery()" should'
@@ -2369,8 +2363,6 @@ public function testGetRelationInvalidArgumentExceptionCaseSensitive(): void
 
         $query = $customer->findOne(1);
 
-        $this->assertEmpty($query->relationQuery('expensiveorders', false));
-
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage(
             'Relation names are case sensitive. Yiisoft\ActiveRecord\Tests\Stubs\ActiveRecord\Customer ' .