Advice required - Is there a minimum age that a baby can travel on a plane?

[Micku5]

Hi,
I am due to have a baby beginning of August and as a belated birthday present I am hoping to go and visit my parents abroad in September. (Dad is paying)
But DH says is not safe for a baby under 6 months to travel. (Have no idea where he got this idea from) and is very reluctant to let me go with such a young baby.
Does anyone know if there is a age minimum for babies to travel?
TIA

We flew with dd1 when she was 3 weeks old. (She was born by emergency cs.) In fact we did two flights in one day, Stansted to Edinburgh and back. The purpose of the journey was to show her to MIL who was terminally ill.

The midwife said it was fine.

the airline we are flying with in july said 7 days, but the mother has to have actually given birth 14 days before flying IYSWIM.
jammy dodger how was the trip to australia because my baby will probably be only about this sort of age and everyone on here seems to think its an impossible and crazy idea to even contemplate.