Willeke Alberti and Ieniemienie. Willeke Alberti (b. 1945) is a Dutch singer and actress. Alberti appeared in the Sesamstraat Kerstspecial 2009, singing "De boom" with Ieniemienie. This song also aired in a normal episode on November 12 External links Offical site IMDb Wikipedia has an article related to: Willeke Alberti Retrieved from "https://muppet.fandom.com/wiki/Willeke_Alberti?oldid=1079533" Categories: International Celebrities Community content is available under CC-BY-SA unless otherwise noted.