Shalom Rav Shlit’a. As you have mentioned in many occasions, there are many different traditions and Minhagim regarding the foods one eats during Pesach or at the Seder, and as Horav Miller Shlit’a often stresses, one should keep always and everywhere one’s family traditions when possible. I visited a newcomer to our community and they offered us some very small deliciously baked complete fishes at a Yom Tov meal. They told me they were leftovers from the Seder and that they had that tradition in his home town in Eastern Europe to eat them. Is there a source for this strange Minhag?

Surprisingly, we did find a source for this unusual minhag and it is mentioned by the Yofe Laleiv (O.H. 2: 473: 5). He nicely quotes the roots of this minhag of his own town, and the origin is in Talmud (Sota 11b, today’s Daf!). He explains the source of our redemption from Mitzrayim, where the women who sacrificed themselves to bring pails of water from the river Nile to quench the thirst of the tortured hard working slaves. On those pails, as Hashem gifted, were also little fish and the nourishment they provided, was a big help in the survival of their men. Yofe Laleiv (ibid) further quotes that those little fishes were reincarnations of the Neshamos of the newborn children that were thrown into the water by the Egyptians.