Is it okay if my wife accepts Shabbos significantly earlier than I do?
Question Continued:
She would like to light candles before my son’s bedtime so that he can watch her lighting.
Answer:
Yes – as long as the candles are being lit after the time of plag hamincha (which is 1 and 1/4 seasonal hours before shkiah).
See more here:
Alter Rebbe’s Shulchan Aruch 261:5
Halacha2go.com article #173: Early Maariv
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