The naughty stool and the laundry room

In our family, we utilise the time-out methods for misbehaving children. We have a naughty stool (courtesy of a tip we gleaned from watching 1 episode of Super nanny) in our kitchen. The length of the time-out will range from short (quick remorse and a willingness to apologize) to somewhat lengthy (very stubborn child and accompanying temper tantrum or, worse, complete denial of behaviour). Generally, the children understand the time-outs are doled out for behaviour that is not acceptable, like hitting or screaming, or not sharing. Once when Ceilidh would not stop kicking Devlin's seat in the van, Devlin said "somebody needs to go on the naughty stool when we get home."
If the initial time spent on the naughty stool doesn't work, or the screaming is at a decibel level that jumbo jets can compete with, then we move on to step 2 - the laundry room. We place the misbehaving child on top of the washing machine in the laundry room since the child can't escape but is not near any harmful objects. It also intensifies the feeling of being left out. Akin to the penalty box.
Now, Devlin is an old pro at the naughty stool routine. He's quick to apologize, and will understand why he's on the said stool. He also stays on the stool for the entire time. When Ceilidh was about 2 years old, she wanted to go onto the stool. If I told her it was time for a time-out, she went willingly. After all, it was something that big kids got to do in her eyes. Nowadays, the novelty of sitting on the naughty stool has worn off. And she keeps getting off the stool. She will even climb down from the washing machine. Once we caught her off the washing machine and playing with her toys during her time-out. (Whoever said you should stay with your child during the time-out only had 1 kid.)
I've now seen Aisling looking at the naughty stool with interest. At this time, she likes to approach her older sibling on the stool and stare up at them and smile. This usually results in a "Aisling is bothering me" scream.
When we visit my family, the laundry room is where the time-outs are served. On top of the washing machine or freezer. And both Devlin and Ceilidh have had some time spent there.
On a recent visit to the cottage, Devlin had a run-in with the broom stick. The broom tripped Devlin, and an owie resulted. Once Devlin was done crying over his boo-boo and the band aids were applied, his uncle Billy told Devlin to scold the broom for being bad. (We sometimes scold inanimate objects like walls, or tables, when the kids run into them and get hurt. After all, the fault for ensuing boo-boo has to lay somewhere, and it's surely not the child who's still unsteady on his/her feet.) Uncle Billy said "bad broom" and Devlin picked up the broom and proceeded into the cottage.
"Where are you going with the broom?"
"To the laundry room. It needs a time-out."