Would Neo Flamvell Garuda's effect activate before Stardust Dragon is returned from the Graveyard?

In a duel I had recently, my opponent used Stardust Dragon's effect to send him to the Graveyard to negate it's destruction earlier that turn. At that time I had a Neo Flamvell Garuda on my side of the field, and at my end phase we were confused as to who's effect would activate first, is there any absolute ruling here?