(LONDON) -- Prince William says his concern for conservation and endangered species, which will be one of his prime areas of focus now that he is leaving the military, was sparked by his mother, Princess Diana, and her tales of her trips to Africa.
"She would come back with all these stories and full of excitement and just passion for what she had been doing and I sort of used to sit there, quite a sort of surprised little boy at the time, taking it all in," William told CNN's Mark Foster in an interview scheduled to air Sunday.
The new documentary special on Prince William will explore what the future could hold for the royal as he eases into fatherhood and out of his military career.
The special program is scheduled to air only a few days after William announced that he is leaving the military to focus on his family and royal duties.
A statement from Buckingham palace said William will "expand his work in the field of conservation, particularly in respect of endangered species." Additionally he will work on charities that help children and veterans.
On Thursday, William filmed a public service announcement for the non-profit organization Wild Aid urging consumers not to buy illegal wildlife products. Behind-the-scenes photos of the filming were posted to the organization's Facebook page and show the prince smiling alongside soccer star David Beckham and former NBA player Yao Ming.
On Wednesday William and Kate Middleton made their first red carpet appearance after the birth of their son at a fundraiser gala for Tusk Trust, a British charity that funds conservation projects in Africa.
William's interest in Africa and wildlife conversation has even affected decorating choices for the family. The nursery for the royal couple's son, Prince George, was decorated with a safari theme.
As William leaves behind his military career, Middleton is easing back into the public eye as she continues to care for two-month-old Prince George.
"Kate is getting some help from her mom, like anyone who has a baby does. She very much wants to do it herself," said Victoria Murphy, ABC News' royal contributor.
In an interview that aired last month with CNN's Max Foster, the prince said he and Middleton plan to raise their son, whom he called "a bit of a rascal," in as normal an environment as possible.
"Where I can be I'm as independent as I want to be, and the same as Catherine and Harry," William said, referring to his wife and younger brother. "We've all grown up differently to other generations and I very much feel that if I can do it myself, I want to do it myself."
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