San,
you must control her now. If not, in future, you will face more problem....When she in your MIL's house, she will alway good lah.
My second maid was tranfer to me after my mother pass away. When my mother around, and i go visit my mother, the maid so good, uruh uruh my mother leg...ans i told my mother, wow this maid so good uruh uruh, the previous onw never do that. You know my mother don't agree with me... I thought my mother too much, still not satify. When transfer to me after awhile I understand why my mother don't agree cos in front of others, she pretend to be very good....