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 who bottom shuffle tend to walk later than babies who crawl (Sheridan 2014). The most important thing is that your child can bear weight. 16 months: With your help, your toddler can now walk up and down the stairs (Sheridan 2014). 18 months: Your toddler will probably be walking well by now, without needing to hold her arms out to balance.