April 2 is Autism Awareness Day and marks the beginning of Autism Awareness Month.

The following celebrities have children who have autism. They range from actresses to singers to professional athletees. They have been outspoken about autism and involved in various autism awareness efforts.

Click through for photos and information on celebrities with children who have autism.

Toni Braxton
Toni Braxton's younger son has autism. She has worked as a spokeswoman for the organization Autism Speaks. Reuters
Ernie Els
Professional golfer Ernie Els' son has autism. Els and his wife started the Els for Autism Foundation in 2009. The Els Center of Excellence is currently in development and expected to be operational in 2015. Reuters
Doug Flutie
Former football player Doug Flutie's son has autism. Flutie is the president and co-founder of the Doug Flutie, Jr. Foundation for Autism. Reuters
Dan Marino
Dan Marino created the Dan Marino Foundation after one of his sons was diagnosed with autism. He also helped open the Dan Marino Outpatient Center at Miami Children's Hospital. Reuters
Jenny McCarthy
Jenny McCarthy's son, Evan, who she had with ex-husband John Mallory Asher, has autism. Her bibliography includes books on being a parent to a child who has autism. Some of her words have landed her in hot water, however. She's come under fire for claiming that vaccines have something to do with causing autism. Whether vaccines do, in fact, cause autism has become a hotly-debated issue. Reuters
Holly Robinson Peete
Holly Robinson Peete's oldest son with husband Rodney Peete has autism. She and her husband started the HollyRod Foundation in 1997, which is also aimed at helping families who are affected by Parkinson's disease. Reuters
Aidan Quinn
Actor Aidan Quinn has spoken about his older daughter, who has autism. He opened up about his daughter, then 19, in a 2008 interview with the Irish Voice. Reuters
Sylvester Stallone
Sylvester Stallone is announced as part of the cast of "Ratchet and Clank." Reuters
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