Purge or keep? Dementia toybox

My only living grandparent, my father's mother Sun, is in assisted living due to advanced Alzheimer's. While purging the apartment this afternoon, I came across an ugly Tupperware box filled with foam letters and beads she liked to repetitiously play with. This was used during the interim period before she entered the facility and was living at home with my father. I'd been eyeing the box up on the wall unit all month but had put aside a house-wide deep clean until today.

 Dementia toybox

Dementia toybox

What to do with ugly sentimentals? What to do with the belongings of people who are no longer aware of what ownership or objecthood mean?