Hi Paul, welcome to the forum.
There are two approaches for nesting lists here;
MULTI-REF FIELD
I personally don't recommend this one at all, but, some like it.
You can add a multi-ref field in your Categories table that links to the Blog Posts in it.
- Advantage - you can use Webflow's nested Collection Lists feature directly
- Disadvantages - you're limited to 5 nested items, you cannot sort or filter them, and multiref fields are difficult to manage in the CMS admin console.
SCRIPT-SOLUTION
Generate your Categories list and your Post list separately, and use script to reorganize them up on screen. I do this a lot for clients, so [message](https://www.sygnal.com/webflow) if you'd like help building it.
- Advantage - easy administration, can do more than 100 nested items on the page, can sort how you like, works with dynamic filtering.
- Disadvantage - requires some code, or a 3rd party toolset.
Have a look at Finsweet's CMS Nest feature as well, you may be able to make that work well for what you're doing.
