My late Grandma was McCausland and from everything I have read they were a sept of Buchanan and wore their tartan. I can find a McCausland crest but no brooch for a fly plaid, so would a McCausland wear a Buchanan brooch like this one with a fly plaid:

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ID:	36524 https://www.etsy.com/listing/8940548...tish-cap-badge (attached)

It's pretty important because I want to get a tatto of the family fly plaid and brooch to honor her memory.

Thanks!