Sir Nigel Archibald Thornberry is Marianne Thornberry's husband and father of Debbie and Eliza. and adopted father of Donnie.
- Tim Curry - English
He played Mr. Park in We Bare Tigers and We Bare Wolves (NatureRules1 Version)
- He is Chloe Park's Dad
He played Dr. Phillip Sherman in Finding Stanley
- He is an fish owner/kidnapper
- In The Wild Ketchums he is played by Ash Ketchum.
- In The Wild Thornberrys spoof for Chris1703 he is played by Simon Seville.
- In The Wild Thornberrys (397Movies Style) he is played by David Seville
- In The Wild Cartoonberries (NatureRules1 Style), he is played by Homer Simpson.