Dotage (noun)

1. The state of being dotingly fond of someone, especially an elderly person.
2. The state of being old and weak.

Origin:

Late 16th century: from french dot "dower" + -age.

Examples:

1. His dotage had caused him to forget many of his past accomplishments.
2. In his dotage, he could no longer make his own decisions.
3. The children were worried about leaving their grandfather in his dotage.
4. Her dotage was filled with memories of her childhood.
5. The dotage of the elderly is a time when they need the most care and support.