Possible Clues:

• Merciful uncle mentioned inside
• Liberal caterer left men cured with treatment
• Lenient, merciful
• Merciful and mild
• (Of weather) mild
• Barrie's lieutenant may have gingered up the play
• Pound this in concrete, to put it mildly
• Mild; gentle; merciful
• - - Attlee
• Merciful Conservative allowed to embrace fellows