How do you know for sure that baby is not hungry at night?

Hi I was just wondering how you know for sure that when baby wakes up at night time that he's not hungry? My son is only breastfed and chn told me he still needs atleast one b/f during the night. For me it is easier if i just feed him otherwise if I don't and he starts crying my 4yr old wakes up and then I don't get any sleep. Jesse is 4mths old and when he does feed at night he drinks alot, just curious about how you know when it is only comfort they want...

Hi,
At 4 months he probably does still require one overnight feed.
When he is 6 months if he is not sleeping through you could try using a rollover feed at 10pm which is done basically to give you confidence that he is not hungry when he wakes later in the night and you can use settling techniques instead.
Cheers Maree