I walked this trail mid morning with my wife and three girls (8, 10,12). This was an easy walk, especially if you stay on the main trail. There is a box that usually has maps at the start of the trail. Plenty of places to stop and enjoy the peacefulness. There is a seasonal bathroom about half way, which can be good for kids. At the top you come Indian Rock, a nice little piece of history and great views of the marsh from the top.
The trail back is pleasant, and spots you step out a little for some great views and/or photos. The tide was lower and there was a small trail off to the right (not on the map), and only accessible when the tide is down, that lead down onto the edge of the marsh. We walked that right along until you get to where it heads back up the hill through some tall (6ft+) grass and in through some tall shrubs before heading up the hill to the side of the last parking lot. We continued down the main trail until the finish at the Penninman House.