Human Body feed
Prediction
Self-produced touch usually feels less ticklish because the brain predicts some of its sensory consequences. Saying that nobody can ever tickle themselves is too absolute: the evidence supports a reduction in typical conditions, not a universal impossibility.
300
Babies have more separate skeletal pieces than adults, often described as about 300 bones compared with the usual adult count of 206. The newborn number is approximate because developing bone and cartilage are not always counted the same way.
1 cm
People are usually slightly taller after a night lying down because spinal discs regain fluid when unloaded. Around a centimeter is a useful rough illustration, not a fixed daily change for everyone.