It means that they've come to realize something... that they rely on each other... and as they realize that they say "Uh-huh."
منظورش اينه که اونها بايد يه چيزهاي رو درک کنن وقتي که اونها به هم اعتماد ميکنن و منظورش اينه که درک کنن "Uh-huh. "اون ميگه"