Yes, Bhagwan Mahavir had one child.

• In his grihastha (householder) life, Mahavir Bhagwan was married to Yashoda.
• They had one daughter, traditionally known as Priyadarshana (also called Anojja / Anojja Devi in some texts).
• She later married Jamali, who for some time became a disciple of Bhagwan Mahavir.

Both Shvetambar and Digambar traditions accept that Mahavir Bhagwan lived a householder’s life before renunciation and that he had a daughter. There is no universally accepted Jain tradition that Mahavir had a son; the main and clear reference is to his daughter Priyadarshana only.