My son jerk or vibrate in sleep throughout night. I don't know what is this but he don't wake up. He is not tired in morning nor he is crying. me what is this. I can see slight arm moment leg moment or shoulder or chest or sometimes lip not twitching but making hunger noise. It happens for 1-2 seconds only in 3-5 minute gap. Otherwise my kid is alright. He is allergic patient and having asthama He is having immunotherapy for dust mite.pls reply Pls tell me this is dangerous?