App to Manage Photos Libraries

I inherited my parents’ Photos Libraries and need to do some work on them, including merging and de-duping.

I’m aware of PowerPhotos from Fat Cat Software.

Are there any other applications that I should consider?

Thank you.

Nello, I would stick to PowerPhotos.

I have both my in-laws Photos libraries and never thought of de-duping them. I’ve gone through (first pass) and deleted a bunch of stuff (blurry photos and similar ‘junk’, photos that came from my family that I have originals of, etc).

I’d love to hear everyone’s thoughts on how to deal with inheriting Photos Libraries (separate from slides, film and paper photos!)… on a separate thread.