my mum remembers her father calling some of his "sisters" sissy, tootie and tiny
A confusion I had, one ancestor I'd thought I knew the name of her, until I saw an official document, "Cis", I'd assumed was short for Cecily or Cecilia - it turned out to be "Cis - for Sister", as the oldest of a brood, that was how she was known to the entire family. No wonder I'd not been able to find her birth. She turned out to be "Annie Elizabeth".
The first name Bridget or Brigid has many variations.Biddy, Bid, Bee, Bride, Bridgie, Brid, Breda, Bridgeen, Birdie, BridieMy Aunt Bridget was known as Sis, she was only girl with four brothers.