I bought this game to enjoy with my three kids and have played the game exclusively using the co-op function. Pros: Nice character design Good/engaging level design All three of my kids (ages 3-5) absolutely love this game a.k.a. It is very child friendly. Cons: The writing is the weakest part of the game. It suffers from stereotypically bad millennial writing and most of the lines are just ripped out of movies (but done in a very lame way). The multiplayer works but is very rough around the edges. The camera will often start following the wrong person instead of whoever is in the lead and it doesn't zoom out to accommodate multiple people playing. Because the camera doesn't zoom out the players must keep closely together or they will constantly have their character thrown off screen and killed. Despite a couple of short fallings I think this is a very solid game and I have no problem recommending it.
I have played this game both on Steam and GOG and can confirm that the GOG version is far more stable then the Steam version. I don't even consider the Steam version playable it is so bad. As a game that I mostly play with my three children I think that Lego Pirates of the Caribbean is pretty good. It was made back when the dev team put more time and thought into the level designs.