Red Envelope from Chineese Girlfriend Parents

Hi, my son has been dating a Chinese girl. For Christmas her parents gave my son a red envelope full of money. What does this red envelope mean? He recently told me that the girlfriend told him she was ready to take their relationship to next level and her parents want to give him another red envelope. Can you tell me what these represent? Is she wanting commitment (marriage). Being outside their culture I am unclear and unable to provide guidance to my son. My son isn't ready to ask her for her hand in marriage however he does love her. They both are recent college graduates- thanks for any information you can provide