This is simple!


She is a friend of yours, so you should help her. I'm sure she is getting paid for her work, so she should also pay you, at least the same amount of money that she would be paying her assistant. She certainly shouldn't be making more money because her assistant couldn't make it and you volunteer for free.


Just ask her, "What do you usually pay your assistant? If she seems honest and sincere, then just say, "sure, I could do it for that."


If your wife couldn't be there to work with you, wouldn't you want her friend to help you out?


Rich