what is wrong with this cory fry

[Harriet]

the fry is about 1 month old now and as he’s just gotten bigger i noticed he has a strange bump under his mouth i don’t think it’s a parasite and he’s the only one who has this out of 50 or so cories i can monitor them all closely because they are split between several tanks he swims and eats normally and i first noticed it a few days a ago but could only get a clear picture and a good look today it kinda looks like one of his organs like his lungs or his heart is in the wrong place as it pulses at the same time he breathes is this just a birth defect? i’m watching him closely and he hasn’t gotten any worse also assuming he’s had this from birth he seems fine and is an inch long