The Guardian Dragon’s Unexpected Mate by Minerva Howe

Dragon guardian Jake takes his job and his duty to his adopted son very seriously. So when Samuel shows up, claiming to have just as much right to his son as he does, since both of their sisters were his parents, Jake doesn’t react well to the news.
Samuel comes from a dragon wing that’s conservative and rather hidebound, and all he wants is to do what he’s been ordered to do. Get his sister’s child and go home. But then he has to fight a bad-tempered jerk to even see Grant, who is the best toddler ever, and to spend time with him.
As winter rages around them, Jake and Samuel finally start to thaw, and Jake sees that Samuel doesn’t want to come between him and his son, not really. Which is when he becomes Samuel champion. Can they find enough common ground to make them into the family they both so desperately need?
This is a dragon shifter mpreg romance.