Can anyone give ideas for mexican rivera family fun in port?

[Already In Love]

We are on a budget and cannot afford to do a bunch of excursions. Our children are 8 and 3. We really are looking for a place we can go that we can just hang out and relax (a hotel that allows cruise passengers to stay for a fee or free) we've heard about Krystal in PV, but we'll also be in cabo and mazatlan Does anyone have any ideas or recommendations for us?

 

Also, has anyone been to Splash Vallarta (water park with water slides, also swim with dolping/sealions which we won't do). The admission prices to the waterpark is quite reasonable but i have no idea how to get there from the pier?

 

TIA!