Classic cat question - how to deal with cat peeing outside litter box (most likely from stress) in a new home?

Moved into a new home, cats (we have 2 brothers) have started peeing in unusual areas (behind the TV, etc). Surprise. But my mother is totally taken aback by what is, unfortunately, very normal and classic cat behavior in response to a new home, a new pet, a new baby, etc etc. And of course, she's angry. In my opinion, this is just part of being a cat owner, but for her it's not acceptable, and if it doesn't stop fast enough for her... I'm wondering if there's anything that can be done other than scolding the cat if we catch him in the act, and putting him in his litter box. I hear a lot of people talking about Feliway online, although it has many bad reviews on Amazon.com.