Despite its generally warm critical reception from Internet-based horror aficionados — and a chilling set-up that delivers its gross-outs with a helping of wit — Grace is a frustratingly dry entry in that subcategory of the genre that deals with the bearing of children. The subject has been mined in movies like Rosemary’s Baby, It’s Alive, and The Brood, and it’s been deconstructed to the point of abstraction — think “body horror,” as in the first Alien film. Director Paul Solet tries to take the concept back to square one, adopting a sober approach to the slowly paced story of a baby who’s not quite right and the mother who loves her.