What information does Edmund give to the White Witch about his family?

Are you referring to chapter 4?

The Queen takes this opportunity( while Edmund eats his Turkish Delight) to ask Edmund a series of questions. She expresses interest in the fact that there are four children, and that one has already visited Narnia and met a faun. She insists that Edmund bring his brother and two sisters to her house so that she can meet them. She tells Edmund that she has no children of her own, and that she would like to make Edmund her Prince. One day, she says, he will become King of Narnia. She warns Edmund that he will hear many negative things about her, but that none of them are true. If his sister has met a faun, she tells him, she will undoubtedly have heard many nasty stories about her, but fauns are not to be trusted. She orders Edmund to keep their meeting a secret, and promises to give him more Turkish Delight once he reaches her home, which is located betweeen the two hills in the distance. By this point, Edmund is suffering from an insatiable craving for more Turkish Delight, and asks the White Witch to take him to her house right away, but she tells him that she will not, and leaves.