Baby who is less than half-year-old: "the newborn calf does not fear the tiger". Baby got the inborn immunity from his mother; therefore, mother does not need to worry too much.

Half-year-old to a year and a half: baby’s inborn immunity is exhausting gradually;

A year and a half to two-year-old: baby gain the immunity again, but the speed of growth was not satisfactory;

Three-year-old baby: he acquired resistance of bacteria, viruses has reached 90% of adults. The period from six months to 3 years old is the weakest phase of immunity. On this phase, parents should strengthen baby's immunity.

First secret: sleep well

Reason: The scientific research shows that the growth speed is 3 times faster when baby is in deep sleep than he's wake up; from 10 pm to 2 am, it is the period which growth hormone secretion is most exuberant.

Five factors for baby to sleep well:

1. Mother’s heartbeats: for babies, the most beautiful song in the world is their mothers’ heartbeats. Mother can hold baby in her arms like feeding him, and also can lie down and let baby bend over on her bosom. Baby will fall asleep soon with mother’s heartbeats.

2. Classical music: baby within 3 months after he was born cannot distinguish day and night, so his sleep can easily reverse. This time you may play some adagio classical music to baby, and baby will know that night arrives when he is listening to the music.

3. Suitable room temperature: the room temperature should be maintained between 20℃-25℃ when baby sleeps, so that baby will not catch a cold. And in autumn and winter, mother should use humidifier or hang some wet towels, wet clothes to maintain the indoor humidity.

4. Quiet environment: some babies are especially sensitive; some slight sounds will be able to wake them up. Therefore, when baby is sleeping, mother should draw the curtain and make the room not too bright; and also do not operate the washer or other electrical appliances, in order to avoid the noise awakens the baby.

Mother's conciliation: if baby does not feel like sleeping and make much noise, mother can hold baby in her arms and pat his back gently, baby will quiet down gradually and fall into sleep soon.

A few words suggestion: the best posture for baby to sleep is by lying on his right arm recumbent.