Is it lawful to continually refuse to allow a son to visit his mother under the the deprivation of liberty act?

This to be a UK thing. From what I read it is for being allowed to restrain someone in a care facility or a hospital. It said nothing about not allow visitors. When you visit was it causing Mom to be agitated to the point she had to be restrained. Really need more info. Most of us are from the US but we do have members from the UK. Hopefully, they will chime in.