"The holidays aren’t just an occasion to give thanks and eat until you pop — they’re also an opportunity to check up on the physical and mental well-being of older family members. More than half of older adults with diagnosable dementia have never seen a doctor about memory or thinking concerns."
Don't jump on every little mental difference you see, and don't freak out if your Grandpa forgets your name for a moment; cognitive ability reduction is common as we age.
And don't feel that you have to deal with it right that moment, or bring it up at the dinner table. Make your observations, check with other family members, and then arrange to have a talk with the affected family member at another time, in a quiet location. Bring another family member for support.
This is a great and timely article, and a good way to keep looking out for our families.