I spent 4 days in Yellowstone with my son about a week ago to celebrate his 18th birthday. I had to go to Wyoming for work for a few days anyway, so I just took him along and extended the trip to include some time in Yellowstone on the way home. We spent most of the time hiking away from the roads, trying to stay away from the crowds since that was something my son always talked about doing. My activity level is a little limited these days after a heart attack about a year ago, and some respiratory problems after my second round of COVID. Those issues, combined with going from sea level elevation at my house to the 7,000'+ elevation at the park, make it hard for me to do much hiking. My son went out of his way to plan hikes that I could do without too much trouble. I know there were others he wanted to try but he knows I just can't keep up. I was really worried he'd be disappointed about having to do the "easy" hikes because of me.
My greatest memory of that trip, (and probably best ever with my son) is hiking through Sentinel Medows early one morning and coming across a herd of about 75-80 bison. We watched them for nearly an hour from about 200 yards away. We decided to move on and came down the trail about 50 yards where it wrapped around a small hill. My son was about 5 yards in front of me when he came to a sudden stop and crouched down. He quickly crawled backward towards me on his hands and knees, quietly "screaming" that there was a huge bison bull 15 yards around the bend. As soon as he said that, we heard the bull get up and start shuffling around. We quietly (and frantically LOL) backed down the trail and up the hill to get a better view. We were now about 50 yards away and had a clear view of an absolutely massive bull that had been bed down right on the trail.
We sat quietly for another 30 minutes while the bull, very much aware of our presence, took his sweet time wandering towards the rest of the herd. We've encountered plenty of bison at shorter distances while we were in the vehicle at Yellowstone and other parks, but that encounter out in the wild was an entirely different experience. They just seem more impressive when you're away from the roads and the crowds. It's hard to appreciate the sheer size of those animals sometimes.
I had a rule with my son while we were out there that it was a cell phone and camera-free zone. I wanted him to focus on really remembering the small details, the smells, sounds, and feel of being out there, and not just take pictures to remember what he thought would be highlights of the trip. That hike was the only time I regretted not having a camera.