Final answer:
Lucy likely wasn't informed about her Aunt Maggie's dementia because her relatives did not want to upset her and may not have recognized the severity of the situation immediately.
Step-by-step explanation:
The most likely reason that Lucy wasn't aware of her aunt Maggie's mental condition is that her relatives did not want to upset her. It is common for families to hesitate to share bad news, especially about conditions like dementia which can be distressing to hear about. Additionally, cognitive decline can sometimes be erroneously attributed to the normal effects of aging, causing delays in seeking medical advice or sharing concerns with distant family members. Symptoms such as having trouble paying bills, increased irritability, and becoming disoriented are indicative of cognitive dysfunction; however, the family may not have realized the severity or did not want to burden Lucy with the news.