Miss Bridget shocks the housekeeper by showing actual tenderness and affection toward the (as yet unnamed) foundling. She follows that up with what could (should?) be construed as a less than compassionate move--she hunts down his mother (a far easier task than you'd expect) and brings her before the magistrate, Mr. Allworthy. Allworthy doesn't condemn her for what she does, he gives her a lecture on morality, assures her he'll take care of the child better than she could've, and then tries to get the name of the father from her. She doesn't give that up, but does so in a way that she earns the approbation of Mr. Allworthy, as well as Miss Bridget and the housekeeper (who were absolutely not eavesdropping, they just happened to hear what happened between the magistrate and mother.
Really not a lot happens here, and Tom is "off-screen" for almost all of it. Still, it's good to get this kind of thing out of the way and the narrator continues to be entertaining.