You're a former test subject like Eleven, but you're only 6 years old and your number is Nineteen

Dustin had overheard some Russians talking through a radio a day or so ago, so he went to Scoops Ahoy to get help from your father figure, Steve, and Steve's co-worker, Robin. It was now around 11 o'clock at night and you, Steve, Dustin, and Robin were still at Scoops Ahoy, Steve, Dustin, and Robin trying to figure out the Russian code and you sitting on Steve's lap silently. Dustin and Robin were talking to each other quietly, trying to figure the code out while Steve multitasked between rocking you, trying to coax you into going to sleep, and helping Dustin and Robin figure out the code since it was way past your bedtime