Chulpani, more correctly Shulpani Yaksha, has no family or blood relation with Bhagwan Mahavir. In Jain tradition, he is known as a yaksha who created an upasarga during Mahavir’s meditation in Asthik-gram. Bhagwan Mahavir remained completely calm and fearless, and because of his equanimity and compassion, Shulpani later became humble and bowed before him. So their relation is one of spiritual encounter, not kinship. ( jainknowledge.com)

If you want, I can also explain this story in simple Gujarati or Hindi.