We are financially-stable professionals, yet my mother-in-law weighs in on our finances and puts down our lifestyle decisions, like a recent cottage purchase. She does not do so with her other child. Advice?

First talk to your spouse, who may be telling your mother-in-law financial information that should only be shared between the two of you. Tell your spouse you don't want this happening, if it is. As for your M-I-L, when she tries to advise you, inform her that you appreciate her willingness to provide advice, but that you have both spoken with financial advisers who have confirmed you've made the right choices. You're happy with your decision, and as such, it requires no more input, as the decision has been made. Then try to change the subject or leave the room to break the train of discussion for a time.