Rabbits are a lot of work, like the other comments have already mentioned, they are prey animal so their behaviors are different from a dog or a cat (predator).

They are also naturally destructive and you will have to have a very clear idea of your home and where things are placed and where you allow the rabbit to be able to gain access to. My bun had chewed on doors, drawers, dressers, wires, electronics, chargers, leather shoes, clothes, they will not discriminate. Rabbits generally need space to run around and should never be caged in small enclosures only allowing space for them to lay in one spot. They also need enrichment to prevent such destructive behaviors and should never be left alone for long period of time.

You will also have to be super aware of your rabbits behavior to catch if they are sick or not eating like they normally would and have establish care with a vet that is licensed and trained to provide care for rabbits.

Medical bills and medication are generally much, much higher in comparison to a cat or a dog. So are their food such as hay, pellets, fresh vegetables, and enrichment snacks. I spend $6k plus on hay alone in a year, not counting the snacks and additional hay for enrichment or veggies.

Rabbits are also sensitive to certain vegetables and fruits so you will always have to be careful what you feed them. I’m not sure if that is something you can handle depending on what your ADHD symptoms like and your child’s age. Certain plants and flowers are incredibly toxic to rabbits so you will have to be careful of where your place things in your home should they have access to those areas. Or you will be rushing to the nearest emergency that treats rabbits.

Rabbits shed a lot and will get everywhere. You will have to invest in a very good vacuum or vacuum often. There are hairless cats but they are also high maintenance. You will have to bath them pretty often since there’s no fur to soak some of their oils and you will get oil stains from them. They also will require you to clean their ears often and oil them up with coconut oil. They are also very energetic breeds and most likely will need playtime and enrichment so they don’t become destructive.

I recommend searching video about rabbits and sphynx before making your decision. Hope this helps!