It's a topic that divides exhausted new parents around the world - should you let your baby "cry it out" in order to achieve sleep, or should you immediately respond to their distress?
One theory suggests that leaving the baby to cry will damage the bond between the baby and parent, whilst others argue immediately tending to the baby reinforces the crying.
While lots of parents choose an option in the middle of the two extremes, a new study has found "crying it out" does not cause any harm to the bond between parents and their babies.
The study, which was publised in the Journal of Child Psychology and Psychiatry, looks into the debate on whether you should leave a crying baby to "cry it out" or respond immediately to them.
The University of Warwick reported they followed 178 babies and their mothers in the UK from birth through to 18 months.
The mothers in the study were asked to fill in questionnaires, asking how often they let their baby "cry it out", rather than immediately tending to them. They measured the 'cry-duration' and 'frequency of crying' right after birth, then again at three months, six months and 18 months.
It was also filmed so outside examiners could assess how the infant and mother interacted with each other.
The mothers in the study were also asked how often their baby cried at different points throughout the day over the same age increments. They filled out a questionnaire reporting how long in minutes their infant fussed/cried during the morning, afternoon, evening and at night.
Professor Dieter Wolke, is the co-author of the study, from the University of Warwick, told The Guardian the study findings suggest parents shouldn't worry too much about which approach they take.
"There are no adverse impacts of leaving infants to cry it out in the ﬁrst six months on infant - mother attachment and behavioural development at 18 months were found." The journal said.
It went on to say that "there is no harmful impact of leaving their infants to cry it out sometimes or often during infancy while a parent is present" including as long as "the infant is safe, and they monitor the infant's crying."
This study also found, that the frequency of "leaving infants to cry it out in the ﬁrst six months in infancy is not associated with an increase in crying duration or frequency of crying up to 18 months of age".
These results were found through the questionnaire, a report from a psychologist and observing the baby with its mother.
Despite what their studies found, the authors said the findings suggest that parents" intuitively know how to best to respond to their infant, and both they and the child adapt over time."
"We neither recommend leaving infant to cry out nor responding immediately" the study said.
The authors said the research did not mean parents should just ignore a crying infant, particularly when it's a newborn.