My Uncle has been stealing/gambling away my grandpa’s money— he has power of attorney [Missouri]

Location: Missouri

I put wills and trusts because it sort of has to do with it since my uncle has access to my grandpa’s money that was supposed to be used for his care, bills, etc.

Backstory is as follows:

I’m going to preface, I love my uncle. He and I used to hang out when I was a kid and he would take me everywhere. However, sometimes those places were shady. This matters because it was me who brought up to my mom and other uncle that I strongly believed my Uncle ‘W’ (we’ll call him) was stealing money from my grandpa. I had no hard evidence at that point but whenever my mom asked about getting better care for my grandpa, my uncle W would give her the run around. He was evasive and was determined to make my mom be my grandpa’s caregiver even though my mom is pushing 70. She thought it was really odd but didn’t want to think badly of her brother until I brought up some stuff that happened in the past that involved my my uncle, grandpa’s car, an indian casino, and a lake. After that, my mom decided it was best to remind my other uncle of this and similar incidents.

A few years ago, my grandpa had my mom and other uncle removed from the trust (not the will) because my mom and uncle had both moved away. My uncle had moved out of state to be with his new wife and my mom had moved just out of state for cheaper rent and better jobs. They both moved back recently.

I believe my uncle W had convinced my grandpa to give him full control of the money because he was still there. I’m not sure what mental state my grandpa was in at the time, but from what I remember, his 2nd wife had just passed and he felt betrayed by my mom and uncle.

Fast forward to about 6-8 months ago, and my uncle moved back to the area close to my grandpa. My mom and uncle both notice that my grandpa is having a harder time finding his way around town and this is when they decided it’s a good idea to look into different care options for him. The problem was that they couldn’t get access to the money nor could they convince my uncle W to relinquish control at the time. He kept giving excuses, wouldn’t give the lawyer’s information (who still hasn’t contacted my mom after they finally did get the info from him).

Within the last couple of months, they finally have a bit more information and my uncle was able to get some rights to help my grandpa. And yesterday, my mom and uncle took my grandpa to the banks that he has his money in and found out he has A LOT less than they expected and that my uncle W has been withdrawing large sums of money at ATMs at gas stations that have slot machines at them. My other uncle hasn’t finished totaling up the amount of money but we estimate it to be somewhere in the $40k range, maybe even more. They closed those accounts and reopened different ones with my other uncle as the beneficiary and my mom after him.

My grandpa is mostly still coherent but he has good days and bad days. They just moved him to an assisted living facility which is why they wanted to ensure they had the money to take care of my grandpa’s new rent each month.

Obviously, I have a couple of questions:

What can be done to remove my Uncle W from having power of attorney over my grandpa?

What laws, if any are being broken here?

What advice could you give to someone in this situation?