Q. See question 3390 above. 2) Is it permitted to eat a roasted turkey on Thanksgiving?
A. Poskim disagree. Rivevos Efraim, and Rabbi Yehuda Hertzl Henkin. (Bnei Banim 3,:37), explain that Thanksgiving is “only a day of thanks and not, Heaven forbid, for idol celebration”. Therefore, they maintain that merely eating turkey on Thanksgiving cannot be considered Chukos HaGoyim.
However, other contemporary authorities disagree. Rav Yitzchok Hutner is quoted as maintaining that the establishment of Thanksgiving as an annual holiday that is based on the Christian calendar is, at the very least, closely associated with Avodah Zarah and therefore prohibited. He explains that its annual observance classifies it as a ‘holiday’ and celebrating Gentile holidays is obviously not permitted. (Pachad Yitzchak – Igros U’Michtavim 109).
Horav Avigdor Miller is known to have been a strong proponent of this view as well, as he maintained that Thanksgiving’s origins indicate that it was actually established as a religious holiday.(See Ohr. Edu)
Horav Shlomo Miller’s Shlit’a opinion is in principle to be stringent. However, in need as in your case, when you are trying to maintain the Sholom Bais of your closely united family when you are also trying to be mekarev them and do Teshuva, there is room for leniency.
We may add, that since in Canada Thanksgiving coincides this year with the first Monday of Beha’b, and those are days of Teshuva and Selichos (some also fast), it would be better to join your family at the evening after the end of the day.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a