I don't want to confuse you, but I think there is a problem with "three times more money than".
If the mother has 100, does this mean that the father has 400 or 300? I believe both interpretations are possible.
I don't think the problem occurs with "three times as much money as", or perhaps it does?!
Perhaps you should say "My father has four times [or three times] what my mother has." or (sounds better) "My father has XX times the amount of money that my mother has."
Aside from the possibility of ambiguity and the other matters raised in the other threads, I don't think I have ever heard anyone say "three times more money". It sounds odd to me, but it may just be me.