Should I be worried that she sleeps less than 12 hours in total out of 24 hours?

It is normal for a 29-year-old to sleep less than 12 hours a day in total. Each individual is different, and some may require more or less sleep. As long as the individual is drinking enough fluids, eating well, gaining weight, and generally in good health, there is usually no need to worry. Enduring the challenges of getting a baby to sleep is a common struggle for many parents, especially as the baby goes through different stages of development.