Did this with our 5 and 10 yo, along with their 70+ grandmother. Great trail from a former road. If you miss the eruption, there is plenty to do and explore until the next.

We got there about 5 minutes after it finished and spent the intervening 2:30 exploring the river, unmarked hot springs, and having lunch. The greatest benefit was the opportunity to watch the geyser’s entire eruption sequence.

Afterwards we visited Old Faithful, and the kids were less than impressed after watching Lone Star.