What should I do?

I’m not too sure what to do. I have a 5 month old baby and live in Australia. My Nanna lives in the UK and has taken a bit of a turn. My mum is an anxious mess with, flying and emotions. Pre baby I would be jumping on that plan 100% to support my mum and also to see my Nanna. I just don’t know if it is the right thing to do with a 5 month old baby. The flight is around 24hours!!! Any one have any experiences with extremely long flights and a little baby? Is this a bad idea?