What's the best resources for researching retirement investing for retirees?

It's a tale as old as time. My retired mother commented on how the stock market's recent downturn really hit her savings. Why is a retired grandmother who is drawing on her savings in 90% medium/high risk equities I asked. Because her ol' trusty financial advisor told her to!

I looked at her account this morning and her entire retirement fund is medium/medium high risk, high fee equity holdings. I'm researching a fiduciary to take over her account but I'm also trying to see if I can help guide her through it myself. Can anyone point me to the best resources or advice on how to help her?

She's about 65, has a pension, 401k and is starting to draw on social security. I've done extensive research on my own retirement funds but know very little about retirement investing at her age.