New Jersey takes and stores blood samples from every newborn for decades

Every public hospital in the UK and Australia does heel-prick tests on newborns AFAIK. (a sharp is used, and a blood footprint taken on a registration card)

Ostensibly for vitamin K need, but I would be very surprised if there have been NO cases of paternity/maternity/identity where the heel prick card has been sought to do some kind of analysis.

https://www.pregnancybirthbaby.org.au/neonatal-screening-tes...

Retained for 18 years. You can (in some places) opt-out. I would be amazed if many do

Storage of newborn screening samples The National Pathology Accreditation Advisory Council requires newborn screening samples to be stored. After the dried blood spot has been tested, it will be stored in a secure locked area until the child is 18 years of age. In some states you can request the card is returned to you after 2 years.

The stored sample is retained to allow for quality control, and may be used for ethics committee approved research after identifying information has been removed.

The sample may also be used for further testing at the request of the parent or guardian, to provide new medical information for the benefit of the family. After a fixed period (dependent on the state/territory), samples are destroyed.

New Jersey takes and stores for decades, blood samples from every new born and then police uses them