When our grandson was little and he was having ear infections like this I tried a lot of things.
This is the way I look at how the body deals with sinus goo.
It gets full of mucus, the mucus has a good job to do, it moistens then membranes so they do their jobs right, it must be clear, thin, draining down the Eustachian tubes and throat. When something interferes with the system an ear infection, eye infection, or tonsillitis happens.
When the thick goo can't get down the tubes they get clogged. They start backing up, get inflamed from the stretched out stress, the blockage, the whole tube starts aching and the liquid backs up then the ear drum starts stretching outward, it can even perforate to let the goo out.
Same thing with the eyes, it's all connected. If there is sticky goo in their head and it is sitting there trying to find a way out the connections between the eyes and sinuses can get plugged with slow moving goo that just oozes out the eyes. Thus an eye infection shows up too.
Tonsils get plugged up and get huge white globs on them, the throat gets white/yellow/light green strings of drainage sticking in it....you get the idea.
I am a firm believer that the goo must be kept thin. Hence the "several hot steamy showers" per day. The moisture helps the goo thin down and move quicker. The water washes away any allergens, it penetrates the sinuses and lungs and if you're really lucky the smell of the soaps and/or meds in the steam will stimulate the natural job of these areas to "rinse themselves" out will happen....you know what I mean, if you smell a tart lemon your mouth waters right? If you smell peppermint the same thing happens, if you smell eucalyptus same thing.
If you google natural things to do for sinus infections a lot of these ideas will come up. I found that the one for peppermint really works for me. I have been sucking on Great Value brand Starlite Mints for days now and the peppermint smell always makes my nose start running when it is strong. I think it is really helping me get over this goo quicker this time.
So, the goo gets thick and "drags" alongside the tubes and other avenues it has to use. It has to get out and finds the way of least resistance. The ears are naturally right there and just below where the goo is so it's often the easiest place for the goo to gravitate towards.
If your child were older I would say give them some over the counter REAL Sudafed. Only 1/4 dose up to 1/2 dose. They don't need a full dose for anything in real life. I buy my liquid Sudafed a locally owned pharmacy. They order it in special for me. They used to carry it all the time but with the fake Sudafed on the market in everything they just don't use as much.
I can't take the fake stuff. It makes my heart race, I get wired up, and my heart beat gets erratic. So I only take a half dose of the real stuff and I feel better quickly and the goo thins out and drains down the right way. Therefor it reduces ear infections.
So, long long long story short. Keep to goo as thin as possible and that should help BUT BUT BUT if your little guy is just not getting better then get the tubes. This little one can end up deaf, hearing impaired, stressed out, sick, poor immune system, etc...if they keep being sick all the time.