The oxidation state of an atom is the fictitious charge that an atom would have if all bonds between atoms of different elements were 100% ionic. Thus, oxidation is better defined as an increase in oxidation state, and reduction as a decrease in oxidation state.
Most babies take their first steps sometime between 9 and 12 months and are walking well by the time they're 14 or 15 months old. Don't worry if your child takes a little longer, though. Some perfectly normal children don't walk until they're 16 or 17 months old.
Babies develop at their own pace. Typically, they start cruising (holding onto furniture to walk sideways) from 8 - 12 months old, and start walking from 10 - 15 months. These ranges provide a guideline to baby's development. If your baby is delayed in achieving these basic motor milestones, consult your paediatrician or physiotherapist for advice.