Hi mga sis!
To start, I am an OT, so what i will share about autism are basically the red flags i see in the kids i handle. Please take note, i am not a doctor, and i am not authorized to give recommendations, etc.
Triad kasi eto (communication, atypical behavior, and social participation)
what i see in the kids i handle , and eto yun nagiging concerns ng parents mostly--> atypical behaviors( stim behaviors, playing with saliva, stomping feet, tiptoeing, spinning, flapping, licking behavior, injurious and self injurious behaviors, tapping, intense/singlemindedness about a particular item, say newspaper, books, or even blocks, different play patterns, etc) for communication (example: making sounds pwedeng babbling na age-inappropriate, not communicating, echolalia, no eye contact, unable to make request/demands known and resorting to crying,etc), and for social participation--> (not relating, parang deadma lang kahit sa familiar na tao, inappropriate social behavior, plays solitarily, etc)
madami akong referral ng kids between 1.5 to 2 years old. before kasi, may mga ibang parents na aabot ng 4 or 5 before magpapa-eval. I am happy marami na mas pro-active, pag may nakita na iba, early intervention agad. But again, take into consideration na baka too much TV time, too much IPAD, no socialization at all, hindi natuturuan yun kid. Dapat ma-weigh in din
lastly, pasintabi, i know it is very difficult to accept that your child has ASD or possibility na may ASD, but in the end, what we want naman is the best for our kids (i consider my students my kids as well, even though mid 20s palang ako, kasi i see them twice or thrice a week and every achievement nila really makes me happy and proud). It takes time to accept. If you need to talk to someone, there are support groups, your doctor, your kid's teachers, and your immediate family.
Hand in hand yun team for kids with special needs. Very important and integral member is, of course, the family.
Kudos to parents of children with ASD who are doing their best to support their child

Saludo ako sainyo