"Cindy Lou Who's" family are big fans of Christmas. Her mother "Betty," her father "Stu," and her two brothers "Drew" and "Lou" do everything in their power to make it an extra special occasion. But young "Cindy" realizes that Christmas is about so much more than just expensive presents and pretty decorations.

Bill Irwin plays "Cindy's" father "Stu". Irwin has starred in many films and series such as A Midsummer Night's Dream and Hot Shots! He is also a critically acclaimed theatre actor and received a Tony Award for Best Actor in the play Who's Afraid of Virginia Woolf? He has been married to Martha Roth since 1990 and the couple has one child. From 2017 until 2019, he starred in Legion.

Molly Shannon played "Cindy's" mother "Betty". Her acting debut was in the 1989 film The Phantom of the Opera. She starred on Saturday Night Live from 1995 to 2001 and was nominated for an Emmy Award for her performance on the show. She has appeared in countless films and TV series throughout her career, including Bad Teacher, Scary Movie, and Evan Almighty. She has been married to Fritz Chesnut since 2004 and has two children. In 2019 she starred in Sextuplets and was in Divorce from 2016-2019.

T. J. Thyne played "Cindy's" older brother "Stu". Thyne has appeared in the film What Women Want and has had guest appearances in Home Improvement and Charmed. He played "Dr. Jack Hodgins' in the hit TV series Bones from 2005 to 2017.

Clint Howard is one of the smallest actors in Hollywood. He is just five and a half feet tall and therefore often plays unusual roles. He plays "Whobris" in How The Grinch Stole Christmas. He started acting in 1963 and has starred in countless films and series since, including Star Trek, Apollo 13, Halloween and Austin Powers. In 2019, he starred in 3 From Hell.

Josh Ryan Evans played the eight-year-old "Grinch". As a young child Evans was diagnosed with a form of dwarfism, which is why he was only 97 centimeters tall. In 1996 he had his first acting role in Family Matters. He also appeared in Ally McBeal and 7th Heaven. Evans suffered from health problems throughout his life and had to undergo open-heart surgery three times. He died from complications resulting from the third operation in August 2002.