A woman has all my baby photos and won’t give them back

My dad was irresponsible enough to give a woman the one half filled photo album of me and my sister to a woman he had only been dating for less than two weeks and met like 3 times? Among other things and money.

She won’t let him get them back nor someone else, like myself. I’m broken up about it because I was planning on showing my son all of them, he’s going to be born in 7 weeks and I have every single scan photo, every single test and well, everything. What little photos left of me through two baby scans done over 20 something years ago, baby pictures and me growing up just gone. My biological mother ripped up and burned every other one of me before she left us at the age of 4, so they were all I had. What can I do? Is there anything? I’m scared she’s refused to give them back because she’s probably already ruined them.