Seeing that it is mother's day today in Poland, (although not in the UK)I thought we'd feature - Mum's the word!
In fact, it's not about saying how much you love your mum.
No - it's a phrase meaning, keep it secret.
To demonstrate this, here's a short video advertising a new year's eve party; it's so good, you don't want too many people to know about it so remember, mum's the word!
