We've had our son on our 2007 R-25 with us since he was 2:
and have been boating with him since he was six months old:

(many more pics in our album)
He loves the boat. He loves his 'room' back in the cave. He keeps his toys and stuffed animals there. We bring him books and a DVD player for movies and, last year, a Kindle Fire. He plays on the dinette table, lays in the forward berth to watch movies, listens to music on the stereo, hangs out and watches the scenery and is never bored. If he goes out to the cockpit he wears a life vest...always. Inside he does not. The law here does not require life vests inside. The reason is that if the boat sinks, the child is unable to get out because they are pushed to the top of the cabin. It makes sense. That being said, we have installed hooks by the door and always hang our life vests up when not in use. He knows where his is always and how to get into it on his own. At night we lock the door so he doesn't wander outside (not so important now that he is 8). He loves to swim but it is only allowed when we are outside with him. Last year he started jumping off of the bow and swimming back to the swim platform. He's a little fish!
Last year I also taught him how to start and stop the outboard (a little 2.2hp) on the dingy and he was so proud when we jumped in the dingy and he started it up and we cruised over to the dock to pick up his mom and came back to the boat without me having to lend a hand. I also let him sit on my lap and man the helm on occasion. He really loves going in circles.
He uses the toilet on his own now but when he was little we helped. He picked it up quickly and we ended up installing an electric toilet, which helped immensely with flushing, which he could not do otherwise. Being a little boy he liked pushing that flush button so we installed a switched breaker outside of the head so we could turn it off when we determined enough time had gone by for a good flush (p.s. make sure the kids have flushed before you get underway, especially if it is a little rocky out. You have been warned...).
He has had friends come on the boat with him and he has a great time with them. When we visit other marinas he is not shy about going out to say hi to the other kids there and spending time on their boats playing. That being said, he has never seemed lonely on the boat. It was one of my worries when we first started that he would be bored and become uninterested. This has not happened. In fact, he loves boating and is the first to jump up to go when I say, 'Does anyone want to go out on the boat?'
We always spend 2-3 weeks in a row on the boat every summer plus just about every weekend. It has made my son better at understanding risk, better at meeting new people, better at being responsible, able to act properly in times of emergency or crisis, and a happier boy overall.
The R-25 is an awesome boat for children. It is very safe and stable. Even in rough seas it is safe. When it gets a little crazy my son just climbs up to the forward berth and watches a DVD, reads, or naps. Sometimes I wonder how he does it. A few years ago we were watching fireworks on the Hudson River for the Fourth of July. When the fireworks ended, hundreds of much faster boats with obviously inexperienced 'captains' came racing down the river creating massive wakes. At one point I was standing with my feet on the side of the passenger seat and my head near the helm seat (at least a 45 degree roll) doing my best to keep us on course and away from everyone else while avoiding capsizing (actually, the boat's stability kept us from capsizing more than me
🙂). Two boats sunk that night due to those wakes. My wife was crying. My son was not. When I talked to him about it afterwards he said that he was scared a little but he wasn't worried because he knew it was a good boat and I was a good 'driver'. He was six. Boating makes children better able to handle what life throws at them so don't be afraid to bring them along and let them get their feet wet.