There are traces sometimes of an absorbed twin.

Can result in chimeric people, & plays havoc with (so called) DNA fingerprinting.
I believe they also get described as "Mosaic" because the DNA differs from body part to body part.

And because I collect 4 leaf clover**, the smell of milk at certain times of the year smells remarkably like the clover when I open the bus ticket (eg) that they get put in. GF lives on a dairy farm.

** Guinness World Record stands at 110,000 - if I continue for 100 years I may beat that!