1 parent nodetype with 2 subnodetypes - show all subnodes in a viewlist Here is the situation: Using D7 and views 3. 

I have made a nodetype 1. 

I have two nodetypes 1a and 1b (node referenced to nodetype 1).

I want to show all nodes (1a and 1b) attached to nodetype 1 in a views-list when showing nodetype 1.

Contextual filters can only show one subnodetype correct.  

Any suggestions?
You will have to use Relationships to pull in data from your other nodes. When you have defined your relations then you will be able to use these in each fields setting:

Relationships:
field_1a 
field_1b

Fields:
// Uses no relation
// Will display title from content-type 1
Content: Title
// Relation field_1a
// Will display title from content-type 1a
Content: Title 
// Relation field_1b
// Will display title from content-type 1b
Content: Title