Here is my trinitarian speculation of the day. If it is heretical then please ignore it.
The tradition speaks of the Father eternally begetting the Son and spirating the Spirit.
I have always considered these to be two distinct inner-Trinitarian actions. But what if they are the same action viewed from two different perspectives? Might we imagine that the Father begetts the Son by means of the spiration of the Spirit? That the one action, viewed in terms of the Spirit, is procession from the Father but also, viewed in terms of the Son, begetting by the Father.
The Son, in turn, gives himself in the Spirit back to the Father in eternal self-giving.
Just thinking ...