Wow, Heather. Too young... My boy is 4, so I'm afraid I do not have any advice. My thoughts and prayers are with you and your son.
Our son had a feeding tube put in when he was 7.8yrs old. He stopped eating and weighed around 30lbs. He was fed through his tube for almost a year before he started eating enough calories to sustain him. We have kept the tube in and still use it for some meds and for hydration in the hot months or when he gets sick. He had an ng(nasal gastric) tube placed, then about a month later had a peg placed in his stomach and then a couple of months after that had his actual feeding tube that is flush with his skin placed. We just have to change it out every few months and keep it clean. Any other questions, feel free to ask.