Tips for keeping lively 18 month old entertained on boat?

[Ashton87]

Hi All - this will be our 4th sailing trip with our little guy (18 months old) - the last 3 trips were comparatively easy because he was either 6 months (just sitting up unassisted), 9 months (newly crawling) or 12 months (newly walking) but now he RUNS everywhere and is a bit of a wild thing. Suggestions for keeping him entertained when we are at sea all day? I intend to take him to the beach and let him run off steam whenever possible and also find activities onshore but trying to come up with solid "plan Bs" in advance if weather is bad, etc.

He loves to read, draw, etc. and is easily entertained by videos (hello lowered standards due to quarantine 2020) but trying to think of things that will keep him physically entertained as well to cut down on the mischief.

We have a 50' trimaran with a very open cockpit so I keep him down below - any recommendations on a good harness so he can be up on deck more?

Thanks!

[psk125]

Puzzles- but they will need to be age-appropriate and supervised. We chartered a Pénichette with two toddlers and set up a playpen in the V-berth with the adjustable gates you can get for blocking doorways and the tops of stairs. Kids loved being able to bounce around with all their toys and stuffed animals. Walks on deck can be fun, but fraught. We used harnesses and leashes on them. It's not easy.

[EvaWills89]

oh I think it will be very difficult. it is best to buy a special leash for children and do mini-walks on the deck. But it will also be good to organize the child's personal space - buy a couple of toys, various trinkets, make a large board, give chalk, in a word, everything will come down

[fourlyons]

We traveled on a 25' monohull with a 16 month old until she was 4 years old. Her brother was born aboard then 16 months old when we moved into a house to build our second sailboat.
Are you back from your trip? How did it go?
Our kids were outside on deck a bunch. We had lifelines and netting and harnesses with shortish theathers to jacklines. I sewed up harnesses with a stap around chest, over shoulders and between their legs.
Our kids never got anywhere close to going overboard, but the harneses and teathers gave me peace of mind that they would stay with the boat if they did manage to go over. They adapted quickly to using harneses. When they were outside we always watched them, but in harnesses we didn't need to hover.
Below, our vee berth had a net door to make the whole thing into a bouncy room. It was important to me to have a spot to put them if I was needed on deck and needed to not worry about them for a few moments.
Lots of fun!
Debbie