If your brother bought the house before he got married, your sister-in-law has no right to divide the house; If your brother bought the house after he got married and there is evidence that it was bought by your parents, your sister-in-law has no right to divide the house; If your brother bought the house after he got married, there is no evidence that your parents paid for it alone, and your sister-in-law has the right to divide the house, which is half of your brother's share.
Divorce can only divide the property of husband and wife, and the original property will not be divided.