\\\\His stomach isnt wobbly its quite firm (bloated). \\\
So presumably we are not talking "fat" here, which is "floppy", the opposite of "quite firm"
I presume that your are saying that his stomach is distended......question is....with what?...gas? .Yes, one can develop and intolerance to food, not as common as people might think, but yes you can.
It doesnt sound a big deal, but if you are both worried, get a routine appointment to see your GP who will "put a hand on" his stomach and settle the issue.