For most of my gun owning life I have been in homes without small children. This meant that securing firearms was not of any particular concern to me. In college I got a locking steel cabinet to keep guns in because I had roommates and well, we drank a lot. Mostly I did not want some random person at one of my roomies impromptu gatherings to stumble into a gun and through idiocy or malice do something dangerous. However except those times I just kept whatever the defensive flavor of the week was out or in my nightstand.
As I have stopped having roomies and my gun collection grew I have kept weapons around the house for defensive purposes. We had a gun or two in every room we really spend time in at our place in Alabama. Fast forward a couple years and insert a toddler. The topic of guns and kids stopped being theoretical about the time he was able to move around.
Since my kid can barely shove food that is put in front of him into his mouth the odds that he could load a weapon are about 0% but I figure it is better to be cautious now while we have some time to figure out workable plans.
To me the obvious solution to firearms and small children (prior to the age where they can mentally understand firearms and be trained which, depending on who you ask is somewhere between 3 and 21) is to either lock guns up or have them under my direct control be it on my person or next to me.
I got a small lockable case for my carry pistol. Small enough to easily fit into my overnight bag if need be. The long gun that has been following me around lately is a folding stock AK. I needed a way to keep it secured. A big case would be kind of a pain as the only ones I have are 4 feet long and bulky. Though I will keep my eye out for one just long enough for my AK's new more compact folded footprint. My solution for the AK was to take a long lock and run in through the ejection port and mag well and lock the thing.
These solutions cost about $20 total. When I am back home we will need to put considerably more thought and expense into firearms security but that is a post for another day.