Help and suggestions? We have a lot to work through

I am at my wits end with my ten year old son. Some brief back story, we adopted him out of foster care when he was almost four. We've done a lot of work with him and fully realize he will probably need extra assistance for years to come. He has exhibited some disturbing behaviors and is seeing a therapist for them.

The big problem right now in the housr is the lying and hiding things. This has been going on for years and he’s just not making any progress. If anything, he’s getting more skilled at lying to me without missing a beat.

My husband and I have worked hard to create an environment that rewards being honest, clearly defining expectations/rules and consequences, and working with his issues but not letting them be an excuse/letting him have free reign.

Today was the motherload - found dirty underwear stashed all over his room (bedwetting is something we are working with his docs and psychologist on), stealing snacks (although we always have food available), hiding school work, stealing siblings electronics, stealing items from his father and I.

I lost my cool today, he got chewed out pretty good about how if he can’t be honest I can’t give him any freedom. His room had been stripped down to the bear minimum so I can find hidden items, all toys are in a common playroom.

We’ve worked so hard to get him to understand that all he has to do is ask if he wants something. When he does, he’s rarely told no unless there is a good reason (ie wanting a snack as I’m about to serve dinner). We seriously praise truthful and forthcoming actions.

We will obviously continue to work with his psychologist, doctor, teachers, specialists, ect. (It’s truly a group effort), but I’m hoping you parents may have some additional suggestions on what I can try that’s worked for you to curb lying/hiding/being sneaky about things.

Honestly as an ex foster child myself you’re worsening his trauma response. You’re adding to his problems the way you treat him. All the things you mentioned is normal in a child who has been abused and neglected and still doesn’t feel safe. To strip his room down, chew him out, etc. you’re making it worse.