Testing Bro-Sis Co.s in separate plans

[Guest Iwonder]

Would some kind soul tell me if I am over-thinking, over-testing this:

A owns 51% of C and 49% of D

B owns 49% of C and 51% of D.

A and C participate in one multiple employer plan.... Plan 1

B and D participate in a separate multiple employer plan.

In Plan 1:

The compensations/contributions/accounts of A must be tracked separately from C.

A and C must test minimum participation separate from each other

Coverage and discrimination testing must be run for A, separately for C within the plan, and then separately for C and D.