γινόντανε χορωδιακά

Unusually perhaps, you might prefer a personal form in English to translate an impersonal expression in Greek.  Since the participants were the family, it would be strange to impersonalise the English translation  "choir singing took place"?  As well as being unnatural, and stilted as a representation of conversation, it suggests in English that since you are not mentioning the family, perhaps other people were involved.  The key word in English will be choir, and you need to work out a phrase around that.  It will not be possible to keep close to the Greek, and remember that this is not a formal choir (χορωδία),  but a group of people singing together in the manner of a choir.

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