Colin Farrell Says He Should 'Check In' on Conor McGregor's Baby

Funny moment with Irish superstar Colin Farrell ... who apparently hasn't done his Irish duty of checking in on Conor McGregor's baby yet.

Farrell jokes that he "should" check up on Ireland's most famous baby -- and then cracks on our photog for not keeping up with Irish politics.

The best part's when Colin tries to zing our Australian camera guy, Charlie, for being an uneducated American.

As for Conor Jr. ... he's chillin'.