I’m in my 12th month of Aveilus and my daughter is IYH getting married and she wants me to sing ‘Boruch Haboh’ at her Chuppah. Is it permissible?
A parent in the year of a aveilus may participate normally in the wedding of their child. This would include singing at the chuppa as this is part of the mitzva of simchas chasan vkalla. [see Shu”t Zera Emes 3:170, Shu”t Divrei Yatziv 329]