It can be a leap. It can cause them to cry more often, ask for more attention, sleep less, sleep worse, eat less, have mood swing and may even be not pleased with many things.
A leap is a sudden change in the mental development of a baby that announces progress. Leaps of all healthy children occur at about the same age, but children show different levels of intensity when they go through a leap.
The first phase is the difficult period which is marked by the three C's and consists of crying more, and being abnormally clingy and cranky.
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