Fairies have absolutely no sense of the passage of time. They are simply so small that they can only conceive of the existence of Now, and so they do not understand the concepts of yesterday or last week or last year.
Thus it was that Tinkerbell arrived at the Darlings' nursery window with no idea that the children within might have changed since last she'd seen them. She arrived with no idea that four years had passed and that some of them weren't even entirely children any longer.
The window was closed, but Tinkerbell's urgency was such that it lent her the strength to lift the frame just far enough to allow her to fly through and into the room. She raced desperately from bed to bed, peering into the face of each sleeping child, but none of them was the face she was seeking. All were boys.
Eventually, her frustration led her to mutter angrily -- though fairy muttering sounds remarkably similar to any other type of fairy speech -- and she abruptly yanked the blankets off of each of the beds in turn before circling up to the ceiling in a shower of fairy dust, still ranting in her musical voice.
The evening was cold -- as is so often the case in London, which is only one of the many ways in which that city differs from Neverland -- and so the sudden removal of blankets brought all seven boys leaping out of bed and drowsily rubbing their eyes. Tinkerbell recognized them all: the Wendy's two brothers, Tootles, Nibs, Curly, and the twins. Only Slightly was missing, but she didn't much care about that, because she had more important matters on her tiny mind. Where was Wendy?
She asked the boys, but they glanced at each other in confusion and sleepy disbelief. Could it be that they had lost their ability to understand her? This was most vexing indeed, and so Tink furiously circled the room, yanking a lock of hair here, tweaking an ear there, and even impudently flipping up John's nightshirt, much to his embarrassment.
Holding his nightshirt down to hide that which was most decidedly meant to be hidden, John was the first to speak. "What in the world is going on here? Are we to stand idly by while we are attacked in our beds by a ... by a ... by an insect of some sort?"
Insect? Insect?! Tink yanked John's hair as hard as she could, causing him to hold his head and shout in unexpected pain.
She then floated right in front of his face and scowled at him, putting her hands on her hips and shaking her head. She asked him again where Wendy might be, but he still did not understand her, though he was now staring at her with his eyes wide and his mouth hanging slightly open in awe. Upon getting a closer look at her, he had realized this was no insect, though he was most certainly having difficulty believing his own eyes.
Indeed, John and the rest of the boys had all forgotten not only Tink, but fairies in general. They'd been gone from Neverland so long that their adventures there seemed to them to have been only dreams and stories. A real live fairy flying around their nursery was rather difficult to believe.
Tinkerbell gave up on John for the moment, and flew to the youngest boy, Michael, in the hopes that a younger child might have a better chance at understanding her. Michael was still confusedly rubbing his eyes, partly to wake up further, and partly to be sure he was seeing this shining, flying creature accurately.
Tinkerbell impatiently stamped her foot in the air, then asked Michael where Wendy might be found, making sure to add even more gestures than usual. Her miming of long hair and nightgown and kissy faces seemed to make some progress.
Michael asked, "Um ... are you asking about Wendy?"
Tinkerbell flew excited sparkling circles around Michael several times, then stopped in front of his face again and nodded vigorously. When he only stared at her, she stood with her feet wide apart, hands on her hips, Pan-like smirk on her face ... and then mimed being hanged from a noose, her neck bending abruptly and her tongue sticking out of her mouth. When Michael did not seem to understand, she chattered at him frantically, waving her tiny hands about.
Michael looked puzzled by Tink's pantomimes, but pointed at the wall and explained, "Wendy has not slept in the nursery for some years now. She has her own room next door."
Tink nodded, gave Michael a quick grateful kiss on the cheek, and flew from the room, leaving seven sleepy and befuddled boys behind her. It was absolutely crucial that she find Wendy as soon as possible. Wendy saved him the last time and Tink had every hope that Wendy could save him again, even if he didn't know it.
Tink was sure. Wendy was the only one who could save Peter Pan.