Ontario mother Karla Begley is in shock after she received an anonymous offensive letter targeting her autistic son, Max.

The letter called her son a "nuisance" and compared him to a "wild animal". The writer also said that the boy should be euthanized.

The letter's author, who claims to be a "pissed off" mother in the area, complains about the boy's "noise-polluting whaling" (sic) and says the boy "scares the hell out of normal children."

"I was shaking when I was reading it," Brenda Millson, Max's grandmother, told CityNews. She takes care of the boy during the summer and the letter came to her house on Friday.

The letter received international attention after musicians Lennon and Maisy tweeted out a photo of the screed. It has been retweeted more than 5,000 times.

Jim Begley, Max's father, told CityNews that he's worried about his son's safety and that police are investigating the letter. The family will press charges if possible.

Police told the Toronto Star they are investigating and consulting with Crown lawyers to see if the letter broke any laws.

Meanwhile, Begley and Millson's neighbours have rallied around the family. Social media users have also chimed in with dozens using the #Love4Maxwell tag to show their support for the family.

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  • 1 In 68 Children Has Been Identified With Autism Spectrum Disorder

    According to the most recent Centers for Disease Control and Prevention estimates, 1 in 68 children in the United States has an autism spectrum disorder, based on health and education records. That figure represents a significant increase from previous prevalence estimates, released in 2012, which estimated that 1 in 88 have an ASD. A separate CDC report issued in 2013 found that 1 in 50 school-age children have an ASD, but that study relied on parental report, rather than official records.

  • Boys Are More Likely To Have Autism Than Girls

    Autism is roughly five times more common in boys than girls, according to CDC estimates. One in 42 boys have been identified with autism, compared to 1 in 189 girls.

  • The Symptoms Of An ASD Can Present Themselves In Infancy

    <a href="http://www.ninds.nih.gov/disorders/autism/detail_autism.htm#233533082" target="_blank">According to the NIH</a>, early indicators include: No babbling by age 1, no single words by 16 months, poor eye contact and more. (<a href="http://www.ninds.nih.gov/disorders/autism/detail_autism.htm#233533082" target="_blank">Click here for more information from NIH</a>.)

  • Scientists Are Not Certain What Causes Autism

    <a href="http://www.ninds.nih.gov/disorders/autism/detail_autism.htm#233543082" target="_blank">According to the NIMH</a>, both <a href="http://www.childmind.org/en/health/disorder-guide/autism-spectrum-disorder" target="_blank">genetic and environmental factors</a> could contribute.

  • There Is No Cure For Autism, But There Are Ways To Treat It

    Autism is treated with <a href="http://www.childmind.org/en/health/disorder-guide/autism-spectrum-disorder" target="_blank">therapy, education plans and medication</a>. Doctors and scientists say that <a href="http://www.ninds.nih.gov/disorders/autism/detail_autism.htm#233563082" target="_blank">early identification and intervention</a> for children with an ASD can help them thrive in academically and socially in the future.

  • Research Shows That There Is No Link Between The Onset Of Autism And Vaccinations

    Even when <a href="http://www.npr.org/blogs/health/2013/03/29/175626824/the-number-of-early-childhood-vaccines-not-linked-to-autism" target="_blank">multiple vaccines</a> are given to a child on the same day, they are still <a href="http://vitals.nbcnews.com/_news/2013/03/29/17516929-new-study-finds-no-link-between-too-many-vaccines-and-autism?lite" target="_blank">not at risk</a> of developing <a href="http://www.huffingtonpost.com/geraldine-dawson-/autism-awareness-day_b_2979117.html" target="_blank">autism</a>.

  • If A Child Has An ASD, Their Sibling Has A 2–18 Percent Chance Of Also Being Affected

    Studies have also shown that if a child with an ASD has an identical twin, the other will be affected anywhere from <a href="http://www.cdc.gov/ncbddd/autism/data.html" target="_blank">36-95 percent of the time</a>.

  • 20 To 30 Percent Of Children With An ASD Develop Epilepsy

    Children whose <a href="http://www.ninds.nih.gov/disorders/autism/detail_autism.htm#233563082" target="_blank">language skills regress before they turn 3</a> have been found to have a higher risk of developing epilepsy.

  • About 10 Percent Of Children Who Have An ASD Also Have Another Genetic, Metabolic Or Neurologic Disorder

    These <a href="http://www.reuters.com/article/2012/01/23/us-anxiety-autism-idUSTRE80M0EO20120123" target="_blank">disorders</a> include Bipolar Disorder, Fragile X syndrome and Down syndrome according to the <a href="http://www.cdc.gov/ncbddd/autism/research.html" target="_blank">CDC</a>.

  • Infants And Young Children Should Be Screened For Developmental Delays At Periodic Intervals

    The CDC recommends <a href="http://www.cdc.gov/ncbddd/autism/screening.html" target="_blank">children be screened</a> when the are 9, 18 and 24-30 months.

  • Keep Reading

    <a href="http://www.huffingtonpost.com/2013/04/15/this-is-autism_n_3064385.html" target="_blank">LOOK: This Is What Autism Looks Like</a> <a href="http://www.huffingtonpost.com/2013/03/20/autism-prevalence_n_2909533.html" target="_blank">Study Shows Big Leap In Autism Prevalence</a> <a href="http://www.huffingtonpost.com/brenda-rothman/autism_b_2733094.html?utm_hp_ref=parents-autism" target="_blank">Autism Is Not a Parenting Fail </a>