Yes! Some dogs can smell it, or just know. I had a rescue pup that could smell when my blood sugar was low at night and jump on me ( I had seizures from low blood sugar and a few other issues years prior to ever adopting him that I hadn’t had for years ). I didn’t realize what he was doing the first few times. He wasn’t a service dog or anything like that, but he would jump on me at night whenever something was off with me. I knew it was serious when he did that, he was so mellow otherwise. Normally it was low blood sugar so I would eat something to appease him, sometimes it was my asthma and I’d get my inhaler. I’m so glad you found a retriever to help your son with seizures:) I hope no pets or people are subjected whatever is going on with this family.