If the club pays for it, it should come under the cap, or if someone pays for it for the club, ie. a third party.
If she pays herself, or Carney pays for her, ie. 'Pay for your mother to move up here bonehead or you will be sacked' then it wouldn't have to be.
As to the whole issue of what Carney has done, and how he should be treated - these are my thoughts :
I honestly think he is an idiot, he obviously is dumb to go out drinking given the recent headlines, but he didn't actually do anything horribly wrong by anyone but himself and the club so I think the media should lighten up a little. There was no incident, no disgusting behavior, no suggestion he was even drunk. People are getting acting like what he did in and of itself deserves severe punishment. This is not the case, he only deserves punishment in light of his previous behavior and only in line with the expectations placed on him by the club.
In fact if as is reported he went out had two drinks and went home without incident, that is fairly clear evidence to me that he is in control of his drinking, as someone out of control would not have stopped at two. I don't want to defend him, as he is obviously impaired in his ability to make good decisions and is clearly not a good example for kids, or a shining light of our game - character wise, but if the club did not make it explicitly clear that he was expected to not only manage his drinking but also to refrain for drinking completely then they have no grounds for further punishment.
The club should suspend him if they told him that is what they would do if he went out drinking, otherwise they should tell him that now and give him a chance to live within the rules. Clearly he should be off the grog, but unless he either broke club rules, or club direction to not drink then he shouldn't be punished. The key here is for the club to be consistent with what they told the player they would do if he went drinking, if the club was so dumb as to not lay down any guide lines about what their actions would be then they can't expect the player to follow them. With the Roosters who have a terrible record of managing problem players I wouldn't be surprised if they gave Carney a slap on the wrist last time and then didn't make it clear what was expected of him in the future, I wouldn't be surprised at all.