How does child remind Silas of the Lantern Yard?

Eppie's appearance brings back memories of happier times, a time when Silas had hope and a future.... a time when he did not think of money and what it could afford him.

How and when had the child come in without his knowledge? He had never been beyond the door. But along with that question, and almost thrusting it away, there was a vision of the old home and the old streets leading to Lantern Yard—and within that vision another, of the thoughts which had been present with him in those far-off scenes. The thoughts were strange to him now, like old friendships impossible to revive; and yet he had a dreamy feeling that this child was somehow a message come to him from that far-off life: it stirred fibres that had never been moved in Raveloe—old quiverings of tenderness—old impressions of awe at the presentiment of some Power presiding over his life; for his imagination had not yet extricated itself from the sense of mystery in the child’s sudden presence, and had formed no conjectures of ordinary natural means by which the event could have been brought about.