There are several things when flying with babies and children. The first is how relaxed the parents are, if the whole process of getting up early rushing around, dealing with family waving you off, then the stress of security, the airport and not really knowing whats happening and what to expect next, then you'll have some very stressed parents. The baby will sense that. Then also there are techniques like ensuring the baby or child is drinking during the climb and descent phases so that the ears adjust, which some inconsiderate parents seem to forget how much it could hurt the baby.
Personally, having flown an awful lot, I discovered the noise cancelling earphones, absolutely fantastic. As soon as you switch them on it just goes silent, makes a flight so peaceful.
The Airbus A380 is a much quieter aircraft, almost silent infact, and for sure the noise will seem more when a baby cries.
