After opening up about her 2 ½-year-old son’s speech delay in August, Jenni ‘JWoww’ Farley revealed on Instagram Wednesday that he was diagnosed with autism.

“This is @greysonmathews with his amazing ABA therapist Nashwa from @wecareautismservices,” the Jersey Shore: Family Vacation star captioned the photo of her son Greyson and his applied behavior analysis (ABA) therapist.

Farley, 32, also opened up about his development to Hollywood Life, saying that although Greyson “isn’t speaking yet,” he is now in speech therapy classes, where he’s “doing amazing.”

Delayed speech is one of several early signs that a child might be autistic, says Dr. Elizabeth Murray, a pediatrician at Strong Memorial Hospital in Rochester, NY and member of PEOPLE’s Health Squad.

“Autism will often impact how a child speaks and socializes, not if they can sit or walk,” she explains. “Early clues include not responding to their name at 12 months of age despite clearly being able to hear, not making eye contact or not showing interest in engaging in simple games with caregivers such as peek-a-boo.”

But, Murray cautions, those signs could also just be normal developmental hiccups. “Many children have delayed speech but enjoy engaging with others,” and therefore may not be autistic, she says. “For example, a child who can always get their point across despite not saying a word.”

As a general guideline, Murray recommends parents use the Center for Disease Control’s checklist of developmental milestones — but to discuss any concerns with a doctor.

“Talk to your pediatrician,” Murray says, adding that regular screenings for autism occur at the 18- and 24-month checkups. “They will be able to provide more detailed screening and can refer your child to a specialist if needed.”

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Murray also stresses that every child diagnosed with autism is different.

“It is important to remember that autism can present as a spectrum of differences with some children having very mild symptoms and others having profound differences,” she says. “The disorder can be so varied that its impact can vary greatly as well.”