Yes in the beginning they might have shown like that … but last 4-5 months ..especially from Devyani marriage track it’s more loyal servant to master .. Kaku is shown more as a strict matriarch .. Till Ladakh trip it was really like Kaku wants virat to indulge in an affair with paapi .. she cannot be that stupid ..I can see her change now ..
kaku’s behaviour with Sai is more towards keeping virat samrat at peace .. she knows pakhi angle starts stirring up and they cannot be squashed … and Kaku has understood virat is more in love with Sai .. he gets mad in her absence .. so she is maintaining a status quo to keep her tied in the house with virat ..But after anniversary bonhomie in ninad famiky .. Kaku will shift camps surely
Samrat's entry made kaku change her behaviour towards Sai... Otherwise, not only till Ladakh trip, the vada revelation track too kaku went with paapi to force Virat to feed her by his hand, birthday track, p pushed sai, but was not questioned, honeymoon track... Anyone could tell that P's zombie walk and cries were because Virat went out with his wife but instead of getting angry with her/ questioning her, she was supported. Till the time they thought that Samrat won't return, they tried that virat- Pakhi had affair, after Samrat came back, these things are in control. Now kaku too knows about Pakhi's obsession for Virat and how they can't control it, so the best way is to take all support from her and support Sai, the opposing team.