My first piece if advice is to get your son to a doctor immediately (yes, that means the ER). I'm not saying that your situation is definitely an emergency, but there are several things that could cause the gurgling you're describing, some of which could lead to chest infections (v. important to treat immediately). Do not take a chance. I think it's probably a bit early for RSV season, but not by much, so who knows. RSV needs to be taken very seriously. However, to me this sounds more like reflux from the little I have to go on here. You may need to switch from the formula you are using to one with the proteins broken down, such as Alimentum. Our son had vicious reflux, and we worked w/ a great ped GI at UCSF. I had originally been breastfeeding, but the doc had me switch to Alimentum formula. (We had tried soy-based formula already, and the problems did not improve in the slightest -- plus soy allergies are relatively common.) At night, after you feed your baby and put him back down (even if you hold him upright for a half-hour+), he could be experiencing reflux, spitting up, and aspirating on it (getting some of the spit-up into his airway and lungs). Foreign substances in the lungs are an extremely serious problem. That is why I think you need to get to the ER *today*. There are other possible causes, too, but why take a chance? I'm not one of those parents who calls the doc at the slightest sign of a sniffle. Potential chest congestion, though, is a completely different issue. Please get your son to the ER and then to the pediatrician on Monday. As for adding rice cereal (or any cereals) to your son's bottle, please do not. I received the same advice from a couple of moms I know, but my son's pediatrician and both of the pediatric GI's he saw (the first one was with CPMC but got a serious illness and stopped practicing, and the second one is at UCSF and has a reputation for being the best in the Bay Area) told us not to thicken his bottle with rice cereal or anything else. All three were quite adamant about this. If your son has reflux, feel free to email me if you want to know more about what worked in our situation. For now, just make sure that your baby's lungs are okay.