Am I legally able to request a copy of the accounting on an irrevocable trust that was never provided to my son, who died 8/9/21 at the age of 32?

The trust was held by an attorney who made us jump through hoops for 8 years just to get a copy of the document. The grandmother was last living of the trust and she died in October 2007. The executor is my ex-husband and only child of the decedent. My son, the only grandchild, was named as beneficiary in full and partial on many of the assets in the trust. Even though we had the document that showed all assets that should have gone to my son, the executor gave him only a few of the assets over time but never gave him any type of accounting nor did the attorney that we received the copy of the trust from. My son was afraid to ask for an accounting because he thought his Dad would be giving him the rest, at some point. We know for a fact that one of the assets was a pension account with my son listed as the only beneficiary to receive the funds at the age of 18. When we called to find out how he could receive the funds we were told that the funds were already taken.