When our daughter, who has ASD among other health issues, was 7 years old, she was really interested in 'everything cellphone!'  She was delighted by the fact that she could listen to her Daddy talking to her in the car and she could (even though limited in verbal communiations) ...she could 'Tell Him' what she saw, even while he was at work and she was with Mama looking out the car window. 
I let her use my cellphone for fun, and while that was before all the "Apps" they have out now for kids...there were still some 'games' on my phone that she loved to play with.  Mama's cell phone was simply the best "interactive Toy" in the house!
One day while I was making lunch, I heard the sounds of a 'strange' woman's voice, echoing through our house.  I immediately dropped my kitchen utensils and ran toward the living room.
"Alli?...where are you!" I hollered.  I felt my blood-pressure literally rise, and my heart began to race.  'Oh my God! Did I forget to deadbolt the front door?...Oh God, I wonder if she let someone in the house?!'...I thought as I scrambled from room to room looking for my little one.  
"Alli! Seriously Honey...where are you? Mommy's getting scared now! Please say something Honey!"  I yelled.
"mmmhmmm....Okay...is there someone there?" I heard the 'woman's' voice say. As it echoed through the house I couldn't quite make out which direction it was coming from.  I ran to my daughter's bedroom.  Threw open the door! She wasn't there.
I ran to our son's room.  We have twin boys who share a room, one of them is also Autistic.  The room was empty.  The boys were at school.  Still the voice sounded as though it was moving through the house!  As I moved, the 'woman' moved.  I couldn't make out what she was saying. But suddenly I heard my daughter talking back to her.   Alli still spoke mostly gibberish...but could say some nouns and verbs appropriately.
"blekkdiish?" I heard Alli say.  "Dear. Can you get your mommy?" I heard the woman clearly say.  "Mama is lunch" Alli responded with a giggle.  "Did your Mommy leave you alone Dear?" The woman responded.
"ALLISON!" I screamed, frantic now and running back and forth from room to room.
I could clearly tell that Allison and "whoever this woman was" were switching from room to room as fast as I was trying to catch up with them. 
"Heehheeehaaa...Mamas phone." Allison giggled in a very muffled sound.  "Do you know where you are Dear?" the woman asked.  "Is there any grown ups there?...Do you feel scared?" she kept asking.
"Oh my God Allison! Where are you! HONEY Please!!" I yelled....
"Dear, I can see where you are now, are you still there?" she asked and Allison giggled again.
As I grabed the edge of the doorway into the master bedroom and pulled myself around the doorframe into my room, I could see Allison sitting there, burried under the comforter on my bed.  She giggled and I quickly noticed the light from my cellphone blaring out from beneathe the heavy covers.  I was panting!  I yanked the blankets off the bed and unveiled my little girl sitting beneath them, a smirk on her face and the phone, lit up as if she was "talking" to someone. 
I grabbed the phone.  "Allison, what the heck?" I said. "Hello?!" I heard the woman ask, loudly! "This is 911 Emergency, is this an adult?!" She asked out of the speaker portion of the phone.  'The phone is on Speaker!' I thought 'Oh my God! she called 911!'
"Yes Ma'am." I said. "I'm sorry! The girl who called you is my daughter, she has Autism! I'm so sorry.  I was in making lunch and I then when I heard a woman's voice, she must have dialed without my knowing....oh my gosh I'm sorry. I didn't even know she knew how to dial the phone. I don't even know how to use the speaker part of this phone yet?" I panted.  Out of breath from my marathon run!
"Ma'am, that's okay. Calm down. It's okay. I just need to make sure, there's no emergency there right?" she asked kindly.  "No....I'm so sorry." I continued. "I was frantic. I thought, cuz it was on speaker, she'd let someone into the house...Oh my God that was scary!"  
"That's okay." she asked me to verify my name and address and made sure everything was alright.  Amused, she said "Your daughter is a very smart little girl. She's got a very sweet little voice.  Don't worry Meredith.  Try to calm down."
After we'd hung up, Allison and I ate our lunch. Later she showed me how to use the 'Speaker phone' on my phone.