Related Clues:

• At the peak of maturity
• First among siblings
• Child with responsibilities, traditionally
• Least green
• Guinness World Record adjective
• Most senior
• Adjective for Cain
• Guinness superlative
• Heir, at times
• Furthest along
• Most elderly
• Least fresh
• First-born of siblings
• Favorite son, maybe
• Pick of the crop