Entity Framework Core Include/ThenInclude to get the data

Question

I have tables in my database with the following one-to-many relations:

a -> b
b -> c
b -> d

which are mapped to corresponding navigational properties in the model.

I want to get data from "a" with all related data from "b, c, d".

If I try:

dbcontext.a.Include(x => x.b)
           .ThenInclude(x => x.c)
           .ThenInclude(x => x.d)

I get an error because this implies a relationship c -> d (instead of b -> d).

Then, if I try:

dbcontext.a.Include(x => x.b)
           .ThenInclude(x => x.c)
           .Include(x => x.d)

I get an error because this implies a relationship a -> d (instead of b -> d).

I'd appreciate help on how to correctly chain the methods.