If the Screaming Baby card is revealed when playing the Father of the Bride ‘Dad Joke’ ability, then the Screaming Baby can be immediately laid down in an opponent’s guests.
If you have no money, then you can immediately discard the Screaming Baby.
The Screaming Baby can be laid down into your own guests if the player wishes but the Ability is not active (I.e. you can still play guests).
The opponent may buy Items to spend their money before spending remaining money to remove The Screaming Baby.