If your baby suddenly starts crying and the baby continues to cry and won't stop sometimes cuddling the baby or rocking him/her can help the baby stop crying.
Also you can swaddle the baby to simulate the womb which can sometimes comfort the baby and help them feel more comfort and then sometimes they will stop crying.
Make sure though that the baby has been taken care of and been fed, changed, burped etc and if the baby still cries and you've swaddled them then it might be a good idea to take them to urgent care just to be checked out.
During the daytime newborns will cry around 2 hours per day which is normal but sometimes they might start crying for 3 to 4 hours per day.
If the baby is crying more than 4 hours per day then something could be wrong such as an illness or the baby is in pain etc.
During the night the baby may cry more for the first 6 months of life.
It's very normal for babies to suddenly cry throughout the night during the first 6 months of life.
After 6 months of age the crying in the baby slows down and the baby will not cry as much.
However another thing happens when babies reach 6 months of age which is separation anxiety which can cause the 6 month old or older baby to start crying at night because they want to be near you or want to be held.
Sometimes just getting near the baby or holding them in your arms and rocking them back to sleep can help with the crying.
The baby could also be in need of a diaper change or want some formula or they could be sick with a cold or flu or other illness.
Usually the sudden crying in the baby is nothing to worry about but you should always check on your baby if they do cry.
Babies are wonderful but they require you to have some sleepless nights and require a lot of work and are a big commitment.