Simplify the following text for a Grade 7 native English-speaking person.
Original: The Siouan ( a.k.a. Siouan proper , Western Siouan ) languages are a Native American language family of North America , and the second largest indigenous language family in North America , after Algonquian .
Simplified: The Siouan languages ( also known as Siouan proper or Western Siouan ) are a group of Native American languages .