This isnt about Andy's mom. Everyone knows that Gauhar gets special treatment. She got to speak to her mom before when she went to the store room once , then she went out of the house and got to see rest of her family. And now gets to speak to her sis.
If BB wanted to be just, he would've treated everyone alike and not given Gauhar the privilege of communication with her loved one since no one else had that chance.
Not sure of how many TRPs Gauhar brings, but I'm going to propose a Salman angle.
Salman and Gauhar have both accepted the fact that he's met gauhar more times than Tanisha and knows her well. In the beginning few episodes, Salman even voiced that he liked gauhar. In the last two seasons though, the contestants Salman suggested have ended up losing despite of being really good. So it's quite possible that Salman decided to stop siding with Gauhar so this doesn't happen to a contestant he supports yet again. But Gauhar continues to get favours from BB due to Salman's favouritism.
This is the blatant favouritism that everyone can see on TV and no one needs a super brain to analyze this issue. So people with 'gauhar syndrome'... dont even bother justifying, or shifting the blame elsewhere.
She gets favoured as she's probably been promised so. No wonder she gets absolutely hysterical when things dont go her way, because maybe her contract says that she will get support on any matter whether right or wrong.