"Tu sais que tu vieillis quand tu as cette seule bougie sur le gâteau. C'est comme "Vois si tu peux l'éteindre"."

Simplified Meaning:

As people grow older, birthdays become more about celebrating the passing of another year rather than making a big fuss. When you’re young, your birthday cake is often covered with lots of candles, one for each year of your life. But as you get older, you might just get one candle on your cake. The single candle can be a playful way of acknowledging that you have had many birthdays already. It’s also a little joke—suggesting that blowing out even one candle might be a challenge as you age. Imagine a grandparent trying to blow out a candle; people might laugh and cheer them on, enjoying the moment together. It’s a way of saying that growing older is a part of life, and we should embrace it with humor and happiness. So, next time you see one candle on a cake, remember to enjoy the celebration and the laughter it brings.