A stroller and foldable frame assembly for a stroller includes a locking mechanism adjustable between a locked position and an unlocked position. The locking mechanism is configured to releasably lock the foldable frame assembly in its use configuration and/or storage configuration by releasably and internally locking at least one of a respective swivel joint assembly of the frame assembly. The locking mechanism includes an actuation element configured to adjust the locking mechanism between the unlocked and the locked position that is arranged spaced apart transversely to a swivel axis of the respective at least one internally lockable swivel joint.