Hi there
It's hard with such short appointments to get straight answers on everything, particularly as GP's aren't usually experts on eczema! Could you ask for a referral to a specialist? It sounds like you could really benefit from seeing a paediatric dermatologist. Whereabouts in the country are you? I know a v good one at St Thomas's in London if that's accessible to you?
With the management - what you want to be doing is preventing dryness as much as possible and keeping the skin moist even when it is looking completely normal. This is important to help prevent flare ups. Morning and night all over plus top ups at nappy changes would be a good way to start. (We did 4x per day with the moisturiser until DD was about 18 months old and she was no longer having flare ups. Now we are down to 1 or 2 times per day)
Aveeno adult products are fine to use. GPs will always err on the side of caution but you'll find anecdotal evidence all over MN of using both the bath oil and the moisturiser successfully with really tiny children.
Then for flare ups don't be afraid to apply the steroid/hydrocortisone liberally until the skin looks completely clear. My GP was always very cautious about this (and rightly so) but when we saw the specialist they were very clear that you have to apply liberally and keep doing it until the flare up goes. If you stop too soon or don't use enough the flare up won't clear. And anti-b's for anything that looks infected.
It's a lot to take in, there are so many options, and it is a bit trial and error until you find what works for you.
How often are you taking him swimming? Just a thought but it might not be helping. We were advised to avoid chlorinated pools whenever there was a flare up, and to not take DD swimming if her skin was very dry, to wash her down thoroughly immediately she was out of the pool if we did, and then to do a thorough slathering in her Unguentum moisturiser.
Sorry this was so long!