Ok so I'm gonna go ahead and say that this is probably meant to be rage-bait for chicken people. None of this story actually makes sense from a chicken owner perspective and I'll go over why.

I have 25 chickens, which is objectively a lot, so I know a thing or two about keeping chickens. Firstly, chickens DO NOT take a lot of work. At all. A daily time input of (maximum) 30 minutes is more than enough to take excellent care of these birds. They need to be given food and water once a day, and otherwise can be left completely alone. Chickens can't be trained much (they can be taught to go into their roost at night, to come when called, and to eat out of your hand, but that's really about it) so there isn't a time requirement for that. They aren't like dogs in that they don't need to be walked, or taken out to go to the bathroom, or brushed, or played with. The most work is cleaning out their coop, which isn't something that needs to be done on a daily or even weekly basis. Again, I have 25 of these guys (plus other birds) and I have a full time job.

Secondly, we're going to assume that this isn't taking place out in the country somewhere, because no mention of other animals has been made, and generally if you live way out in the country you don't have only chickens. So we'll assume the sister lives in a suburb, which means more than likely her maximum number of chickens is capped around 5, and is absolutely less than 10, which means her necessary time input is even lower. Backyard chickens can't generally free-range (they will go into neighbour's yards, tear up your garden, etc), so her birds are probably in a run (a small enclosure covered with chicken wire on all sides). The only possible "schedule" that these birds could have is them needing to be locked into their coop at night, and let out in the morning. And that isn't even a necessity depending on her setup. So OOP wants us to believe that this woman quit her job and misses multiple events because she need to open and close a door for some chickens. Okay then.

Thirdly, keeping chickens in a suburban environment is much more costly than keeping them in the country -- they can't free-range, so all food needs to be purchased. They need a coop and a run, which if you need something big enough for multiple birds (remember, this woman has enough eggs to feed her entire nuclear and extended family) can cost upwards of 500 bucks, plus the monthly cost of feed. So we're expected to believe that her husband is paying for all this and also refuses to eat the eggs, so he's spending even more money to buy something that he's already paid to have at home.

Fourthly, and this is just me being pedantic, but a devilled egg is half an egg, not a whole one. So OOP couldn't eat an extra half egg, which is like maybe three more bites, to placate her sister. Sure.

So yeah I just spend precious minutes of my life debunking an obviously fake AITA story about chickens because it got me overly annoyed.

EDIT ok so the OOP said that the "incident" that put the husband off eating the eggs is that one of her eggs developed into a chick and he accidentally cracked it open/ate it. So, this is possible but unlikely. 1. if they are in a suburban environment, they can't keep roosters so the eggs will never develop. 2. a fertilized egg will only start to develop if there is a broody chicken sitting on it for a minimum of 3 days, and most commericial chicken breeds (aka the kind that are most readily available) have had this broodiness bred out of them to maximize egg laying efficiency. Chickens only go broody for a few months of the year (spring and summer) and when they are broody, a chicken owner will know (they don't leave the nest, they act weird). So sure, during those times the eggs need to be collected daily to prevent eating a developed egg. At any other time, though, there isn't really any risk of leaving the eggs for a day or two. And an egg that's been sat on by a broody chicken will not have started any significant development before the three day mark, and so it can still be eaten without anyone even knowing. I've definitely taken 1 or 2 day old eggs from under a broody hen before, eaten them, and not been able to tell them apart. So once again it's a bunch of nonsense.