The gender of the baby was revealed in April when the chimneys of Battersea Power Station in London were lit up in pink to show Mummy Pig was expecting another girl.
An hour-long special titled “Peppa Meets The Baby” will premiere on May 30, as Peppa and George get ready to welcome their new sister.
Evie is due to appear on screen in the series from autumn.
A special set of stamps has been issued to mark the 20th anniversary of the series, featuring Peppa and her friends.
The stamps include Peppa and George, Suzy Sheep, Danny Dog, Daddy Pig, Mummy Pig, Grandpa and Granny Pig in the main set.
The series, co-created by Neville Astley and Mark Baker, first aired in 2004 on Channel 5 in the UK.
It has since been broadcast in more than 40 languages and is available in over 180 territories.
