What To Do With My Retired Parents Money

My mom is 81, and she has a federal gov. pension and around $850k in the market in various ETF's, Mutual Funds and individual stocks. These investments have obviously done well over the past few years but I'm concerned about a market correction and her losing a sizeable amount of this.

She's in an independent community and will likely need assisted living at some point in the next few years. Her pension covers the monthly independent living costs but she has about $2k in monthly expenses that she needs to cover. What would you recommend we do to put her money in a safer investment that we could easily pull from to cover monthly expenses or somewhere that would provide a monthly dividend / income?

Edit: The $850k is in non-retirement accounts so she'll owe capital gains tax if she sells.