Delayed language development - just a late bloomer, or something serious?

[hitchhike42]

My nephew, who is almost 18 months old, has met most of his motor milestones. He scampers all over the place, and is even able to make his way up and down stairs.

What I'm concerned about, however, is his mental development. He doesn't appear to understand any language at all, let alone respond to his name or simple gestures. The only sounds he makes are moans and grunts, with nothing remotely similar to a consonant or "babble." The moans are especially apparent when he's holding an object that has piqued his interest - he holds it with one hand and uses the other to "stroke" it (by which I mean, he opens and closes his hand repeatedly so that his fingers sweep across the object, back and forth) whilst making a long, continuous moan. This behavior can go on for minutes at a time until he either gets bored or something else catches his attention.

I should note that there is one gesture that he does use to communicate - he holds his arms up towards an adult if he wants to be picked up. However, that is the extent of his ability (or willingness?) to communicate with us. He doesn't wave good-bye or hello, doesn't hand objects to us, and is generally oblivious to anything we say, verbal or gestural, to interact with him.

Are these valid reasons to be concerned? Could my nephew possibly be autistic or otherwise developmentally delayed? I'm asking for outside opinions because my sister and her husband are reluctant and keep procrastinating to get him screened.

Also, although I consider autism a very real possibility, I've also been suspicious of hearing impairment. Children's TV shows such as Team Umizoomi and Bubble Guppies tend to grab his attention very easily, and while watching them he can break out into squeals and giggles, like any other kid his age. I've heard various sources claim that partial hearing loss can result in toddlers being receptive to specific frequencies. Is it possible that my nephew is able to hear the high-pitched voices and sounds of these TV shows, while human voices and "real world" sounds seem like nothing more than muffled hums?

Thanks in advance. Any and all input is appreciated - I really want to convince my sister to take whatever preventative measures are necessary!

[Majikat]

at the age of two my autistic son literally only liked to play with 2 different toys showed no intrest in new things till this day still has no interest in opening gifts... at 18 months he should have interest in wanting to build the lego... the stroking thing that he does is definatley a sensory thing... autistic children tend to appear very independent and dont really care to have attention... does he have any interest in other children? that is a big thing....
do you notice if he gives you eye contact... its something you really have to pay attention to... my son at that age would literally sit in his room all day and sit in the corner playing with a single toy! he never used toy cars how they are supposed to he would only turn it over and spin the wheels... pretend play is a very impotant milestone that you should be seeing at this age such as pretend to feed a toy doll or animal... vroom cars and so on...

please do not be afraid to bring it to her attention... a lot of parents are in denial when something is wrong with their child but you need to explain to her that her denial will not help her child... early intervention is extremly important and it is a very long road to get a diagnoses and therapy... he sounds so much like my son it is unbelievable!

[hitchhike42]

I don't think I've ever seen him open or close a container - he either does that "stroking" behavior, or just drops/throws it away if he isn't interested. I got him a set of Duplos (basically jumbo-sized Legos made for toddlers) for Christmas, but he shows little interest aside from sliding them across the floor.

While I'm obviously not around him nearly as much as his parents are, he seems to be a very mild and content kid. He may start to cry/whine occasionally (for example, if an object is taken away from him), but he's easily soothed. I'm actually quite surprised by how mellow he is, based on experience with other nephews and nieces from another sister.

He also seems "independent" and doesn't actively seek attention from others. If we don't keep an eye on him, he'll wander off and explore the house or area without a second thought.

But as for your overall question, yes, he does seem to have repetitive play behaviors. He seems to have a rather limited set of behaviors when it comes to interacting with objects, and doesn't experiment or try novel things like stacking blocks.

[Majikat]

hearing loss could be a possibility and should always be tested in this kind of situation... does his play seem to be very repetitive? like spinning opening and closing things for long periods of time? he defiantly needs to be assessed he sounds just like my son was at that age who is autistic... my son was on time with all his motor skills as well except for fine motor skills which i wasnt aware of until i had him in occupational therapy... does he have tantrums and is hard to handle does he like attention?