<human>: It's not just trivial stuff that he throws away, either. He's thrown away my notebooks and textbooks, my mom's textbooks, my sister's old sketchbooks (which she obviously values a lot) and many other things. It's to the point where every week before the recycling gets taken out, my mother sifts through the recycling bin to make sure my dad didn't throw away anything important or valuable. There have been times when he's thrown away papers with sensitive information like bank statements and old pay stubs.

I can't speak for the countless times he's thrown away my mother's belongings, but once, he threw away an acceptance letter I had received from a prestigious summer program, which made it so I couldn't attend, because I found out way too late.

Even when we leave sticky notes on things telling him not to throw them away, sometimes he'll still throw them away. Even if sticky notes would prevent him from throwing things away, I think it's infuriating that we're being held responsible for our dad essentially violating and disrespecting our personal boundaries. My mother disagrees and thinks that we're "compromising" if we agree to do this.

We've tried talking to him about this repeatedly. He has a poor memory, so he doesn't remember throwing things away which makes it difficult for him to take what we're saying seriously. He also becomes defensive, since he's technically doing us a favor by cleaning the house. The thing is, it's something he does entirely of his own volition. I'd be personally fine with being left to clean myself if I had the assurance that my belongings are safe.

I don't know how else to approach this situation to get him to stop throwing things away without telling us and to get him to take us seriously. Our mother isn't much help with this, as she's been worn down to a state of resigned acceptance with this issue. How should I move forward with this?

Summarize the given text in a few sentences.
<bot>: Dad keeps throwing all of our stuff away without telling us and won't take us seriously when we try to get him to stop.