Hi Harolt24! Blount is a great cruise line and the itinerary you’ve chosen sounds wonderful, but it’s definitely not designed for kids. Hopefully all of this was explained to you when you booked, but the Blount website even says kids should be 14 years or older:
http://www.blountsmallshipadventures.com/why-small-ships/is-it-for-me/
We've carefully built our cruises for experienced travelers. The kind of people who are ready to take a break from the hustle, bustle, and chaos of the big ships. With that in mind, we welcome older children, ages 14 and older into our family of explorers.
I also took a quick look at the deck plans for the Grand Mariner and didn’t see any rooms designed to hold 4 people. I guess small kids can share, but in the rooms with a third bed it seems to always be an upper bunk.
I know Blount can be extremely accommodating to special requests and I imagine the crew would literally dote on your kids because it’ll be so different from any of the passengers they normally have. I just don’t want you (or the cruise line!) to be surprised by anything.
Keep us posted – we’d love to hear all about your trip. Happy cruising!