Except (a) the OP carefully placed the laptop where it would not be affected by persons sleeping, tossing, or turning (a1) only after discovering simply taking it away from her daughter wasn't effective; (b) we don't know the style or age of the OP's mattress and box spring (i.e. the latter could very well consist of springs; and (c) we don't know the force with which her daughter "sat" on the bed.
One would expect this mother would know that/whether this daughter normally enters the mother's room and normally sits on the bed.
It appears neither is normal behavior for the daughter or the mother would not have placed the computer between the mattress and box spring. Ergo: snooping. The result of the snooping? The daughter broke her own computer - the computer to which she had been denied access but ignored that restriction, forcing the mother to hide it.
No. The damage would NOT have been the fault of the
person being punished, and the OP would not be asking if she should be mad.



Okay, if that's what you want to think... remember, the OP only hid the laptop after simply taking it away from her daughter wasn't effective. It seems the daughter still accessed
and used the computer anyway.
I'm a little confused over how many times the OP is going to have to repeat that
the laptop was placed in a spot that is not normally used by anyone. Apparently it's even unusual for anyone to even sit on her bed. Maybe there's a chair (or more than one chair) in her bedroom for people who wish to sit?
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In that she purchased, or allowed her daughter to purchase, a laptop computer? You may be right... but then shouldn't we ascribe fault where it TRULY belongs? No, farther back than that - all the way to Adam & Eve?
True - but the OP seems the type who, had
she done the damage, would have simply replaced the computer...
without polling the DIS!!!