 Partners therapy is extended indefinitely.The partners share their first (in a flashback) and third kisses in "The Parts in the Sum of the Whole"; the second occurs in "The Santa in the Slush" when Booth and Brennan agree to kiss under mistletoe in front of Caroline Julian, an attorney Booth frequently works with.Nearly every episode after season three ends with a scene of Booth and Brennan bonding, which become increasingly romantic over time, reflecting the ever-growing affection Booth and Brennan have for each other.