litter mate 

Original definition refers to a group of baby animals born to the same mom such as a litter of kittens or puppies.

New definition: people who share your birthday and therefore same astrological influences.

I just checked out my birth day online and found out that there's a ton of famous people who are my litter mates.

Because we share the same birthday, my best friend and I are litter mates.

litter mate by angeet June 5, 2010

Littermate 

Persons to whom there is a deep connection and shared outlook on life. Someone you've known forever even though you just met. Close as family but without the baggage.

Similar to My Brother From Another Mother or My Sister From Another Mister

"Are they dating, or related?"

"Neither, they're littermates."

Littermate by Angry Sky Daddio June 24, 2024