Deck to cuddy cabin repair help

[rsafr]

I own an S2 5.5 Grand Slam and during my Spring cleaning, I noticed a gap opening up between the side of the cuddy cabin where it joins the deck. It looks like it was caulked or maybe sealed originally. The gap starts at about 3/4" and runs for 8-10" narrowing down all the way.
Do I need to reinforce the flange that is accessible in the cuddy cabin somehow or just use a good adhesive/sealant caulk to close it up?

Hoping someone has some good experience with this and can offer their tips and advice.
Thank you
Rich

 

[Picflight]

This might not be a specific boat issue but rather a sealing problem or prior repair gone bad. Post detailed pictures of the problem area with perspective to get a more detailed response.

 

[rsafr]

Thank you. I'll get the pics and update my post.