From she was a child she had never liked this uncle of hers, he usually bullied her if there are any opportunities and even hurting her physically multiple times like kicking her, throwing her to the pond, and etc.
When Fang Wenna was younger she was timid and shy that is why even with the bruises she had she never told her parents nor her grand parents about the abuse she had received from her uncle.
Furthermore, during those times her uncle was still playing the 'innocent and good-natured' uncle so who would believe her if she said something about ? Added the fact that she is not used to speaking, they would only say that she was being instigated by her grandmother who hated Fang Jianghu's existence the most.