Alicia Keys' sons learned to lipread to speak to her

Alicia Keys' sons have learned to lipread to speak to her during her silent days on tour.

The 39-year-old singer - who has sons Egypt, nine, and Genesis, five, with husband Swizz Beatz - taught her sons how to read her lips for the days she has to save her voice while on tour.

This year, Alicia will be packing up her kids and hitting the road for back-to-back dates across Europe and North America throughout the summer months for Alicia - The World Tour, where their lipreading training will come in handy.

Speaking to Jo Wiley on BBC Radio 2, Alicia said: "The only thing is that it's really hard because a lot of the time I have to save my voice. A lot of the time I cannot speak, and I also have to sleep because if you can't sleep you can't sing.

"Kids don't wanna sleep, they just wanna be up all night. I have to manage how to do that, but they're very good at reading my lips. It's a good writing exercise, they'll write it on paper."

The upcoming tour will mark Alicia's first tour in seven years, after previously bringing her eldest son along with her for her 2013 Set The World On Fire Tour.

The two youngsters are looking forward to travelling across the globe with their superstar mum, and are even hoping to take over with a special performance of their own.

Alicia added: "Genesis, he claims he wants to come on stage and sing with me. I'm surprised because he's a little shy, he's a little introverted. He doesn't like to be in big crowds, so I don't know if he'll actually do it, but maybe he will so maybe we'll practise something.

"Egypt, when he was on tour with me before, he'd beg me to come on stage every night and I had to tell him, 'No, you cannot come on stage every night.' I don't know now, who knows I might have them come up in a classical piece."