Possible Clues:

• Chanted song the wrong way - it's the drink
• Spanish spiced wine
• Spanish sweetened wine drink
• Grain, as distilled into alcoholic drink
• Gran's A1 compound drunk in Spain
• Drink making son more ill-tempered in speech
• Punch served with paella
• Fruity wine
• Performed the song in return for a drink
• Drink's not so cool, one might say