Mathias Blackstone is either Seattle's own version of Scrooge or Santa Claus...

Mathias Blackstone has a reputation for ruthlessness. He's in the procurement business: whatever you want - gold, diamonds, secrets - he can get! But there's another side to his operation he prefers to keep quiet: every Christmas, Mathias Blackstone procures wishes....

But despite his ability to deputize for Santa, something is missing from Mathias's world, and has been since the death of his young son. Then he meets children's writer Jacqueline Randell. For one of his young clients, meeting Jacqueline Randell is a wish come true And the more Mathias Blackstone woos Jacqueline, the more he begins to suspect...that Jacqueline Randell is his Christmas wish, too!

This is the summary for The Miracle Wife:

Five-year-old River Sierra wants a mother - a mother just like the beautiful fairy in her storybook. So when J.J. Randell turns up on her daddy's doorstep it seems her wish has come true. Only River's daddy is less convinced. Raven Sierra has turned his back on love. Now he's torn between his tortured past and his little girl's dreams... J.J. realizes the situation is hopeless. But River is convinced that her miracle mommy can do anything - even persuade her difficult daddy to take another chance on love!