chat_history: ['My son had his 4th birthday a couple of weeks ago.', "How did it go? What'd you get him for a gift?", "He got a remote control excavator, and had a lot of fun at his party.  It's crazy how fast he's growing up, though."]
sys_response: It seems like all those years just flew by, huh. At least now he's getting old enough to start remembering all these great times!
situation: My son recently turned 4.  It's hard to watch him grow up so quickly.