If your baby is not sitting up by 9 months or is not using both hands to play while sitting by 12 months corrected age, talk to your pediatrician. (verywellfamily.com)
Regardless, the cat is out of the bag and the Catholic church better move fast to change things drastically and correct this age old problem. (religion.blogs.cnn.com)
Ideally, catch up growth should happen by the time a baby is 3 months corrected age. (verywellfamily.com)