Honestly, bring it up to your neighbors. Just be polite about it “hi, my name is (insert your name here) I am your neighbor, I live (describe how close you are), I’m sorry to bother you, but could I please have a minute of your time? The fence line of your yard is close to our son’s
bedroom, and while I am sure they are good dogs, they can be loud and their barking keeps our son awake. Is there anyway that maybe you could bring your dogs inside at night? I’m sorry to introduce myself this way, but I am unsure of what else to do.”
Believe it or not, this may actually help you foster a friendly relationship with your neighbor as long as you approach them calmly and politely (don’t be an “Karen”)
Psychological studies have shown that by asking people for favors, you can grow closer to them quicker (the favor here being allowed a moment to speak with them and asking them to put their dogs inside at night) it may sound petty, but it is because while we don’t like being indebted to others, there is a sense of power or pridefulness about having others in our “debt”- the sense of superiority, however small, that we gave them something they needed but could not get for themselves, and they had to acknowledge that they needed us.
Yes, this applies to even the smallest of things.
It can form friendships, or resentments such as if after the favor you act ungrateful/unsatisfied, or if you never reciprocate.
Honestly, most people will appreciate it if you try to resolve the problem by talking to them about it. Your neighbors probably have no idea that their dogs are bothering you, especially if the barking occurs far enough away from their house that they can not hear it themselves or the sound is faint enough they don’t understand how it could bother anyone.
This could also be an ice-breaker, and years later you will laugh and tell the funny story about how you became friends because their dogs’ barking kept your son awake.
Sounds silly, but the my Maid of Honor made included in her toast at my wedding about how we became close friends after I punched her in the face shortly after we first met, lol.
Go over there, be friendly, introduce yourself, shake hands in greeting, and calmly bring up the problem and ask about a possible solution like a rational adult.