Turning 21 is a major deal for many young Americans and in reaching the milestone and with it the legal age for buying alcohol, 21st birthday bashes can go hand in hand with copious amounts of alcohol consumption.

Not for singer-songwriter Demi Lovato who rolled up her sleeves for charity, Free the Children, as part of a volunteering trip organised by Me to We.

She took a group of close friends and family on the trip in the Maasai Mara region to mark her birthday on Tuesday.

They are visiting and volunteering in communities supported by Free the Children, getting to know local students and residents and helping to build a new Free The Children school.

Lovato, a Christian, has also taken part in a water walk similar to that undertaken for hours each day by young women her age in parts of Kenya just to collect clean water for their families.

Cultural highlights include a sunset safari and a traditional beading session with artisan Maasai Mamas.

"With 21 being a milestone birthday, I wanted a memorable and meaningful way to celebrate, rather than throw a big birthday bash," says Demi.

"I knew travelling with Me to We and volunteering with Free The Children would give me the opportunity to have a life-changing experience I would never forget, with the people closest to me. Also having worked with the organisation over this past year it's been great to see first-hand the wonderful work that is being done as a result of all the incredible efforts of young people around the nation."

Craig Kielburger, co-founder of Free The Children and Me to We said: "Demi has been such a generous supporter of Free The Children. We couldn't be more excited to have her travel to Kenya this summer and celebrate her 21st birthday with us.

"On behalf of the entire team, Happy Birthday, Demi! As they say in Swahili, 'Asante Sana' for all of your generous support you continue to provide to our organisation. We hope this year is your best year yet!"