Anna Friel penned letter urging daughter to become Tiger Protector for the World Wildlife Federation (WWF)

In the letter, the 'Pushing Daisies' actress wrote: "Well, 2016 has been a terrible year in many ways and seen so many special people leave this earth but for the first time in conservation history, we've seen an increase in wild tigers.

"Your favourite animal has depleted in numbers by over 95 per cent in the last century but we are starting to turn that around and I would love for you to be a part of the biggest conservation success story in our time."

Anna also urged her daughter to "never grow out" of seeing the good in the world around her, as it is "important" to protect our planet.

She added: "It gives me so much hope for the future, because, through hard work and support, we can make a difference. Since you were born I've protected you like a tigress protects her cubs and I know you will do the same.

"My angel girl, never grow out of seeing the magic in the world no matter how bad it seems. Talk to your friends and encourage them to protect each other and our planet too - it's more important now than ever."

The 'Limitless' actress also backed 'The Tiger Protector' book written by children's author Jeanne Willis, which can be chosen as a gift when a person gives £5 to the WWF charity.

She said of the book: "A good bedtime story can stay with you for life. It can inspire, educate and spark that little bit of magic in the world - something I think we all need at the moment.

Being the next generation to protect endangered species like the tiger, it's really important to me that our children feel a connection at a young age and understand that they can personally make a difference. A good storybook like The Tiger Protector and getting involved in the #iProtectTigers campaign is a great way to inspire them and us."