From this chapter it feels like the mom is the man of the house who's desperate for her children to be successful artist, and dad just goes along with it because he thinks they are/will be happy about it but for some reason it also feels like later he'll find out that Kohaku isn't happy with constant pressure and will step up, tell her not to worry about it and handle mom who will then realize that she's been too overbearing. Still not sure about the older sister though - yandere siscon/arrogant prodigy/some weird way of looking out for her little sis? It could go either way at this point.