We are expecting a second child soon. Once my wife's maternity leave is over, should we pay our helper more, since she will have two kids to look after?

It will be good if you can discuss with your helper or her agency if she is agreeable with the amount of increment or if she is okay to continue her service. I have a few friends paying their helper slightly more when their second child came. One of my friend's helper decided to terminate her service when their second child came as she said she cannot cope with all the duties i.e. household chores, cooking, looking after 2 children.