If my children go to bed before Tzeis, how early can I count Sefiras Haomer with them?
Is there a difference between preschool age and elementary age?
Answer:
The Alter Rebbe writes (Siman 489:12) that it is appropriate to wait until Tzeis Hakochevim to count Sefira, however, he mentions that the Minhag of the average person was to rely on the opinion that one can count Sefira from Bein Hashmashos. However, before Shkiah one should not count at all, if one mistakenly counts before Bein Hashmashos, they should count again, but without a Brocha.
So, if it is difficult for your kids to stay up until Tzeis Hakochevim, they may count during Bein Hashmashos (i.e. from a few minutes after shkiah).
וראה גם שם יג ויז. תצג, ט.
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