Hi,
As per the above mentioned description, I see that you have lost your movies related to your family. In your case it is not a impossible thing to get back your lost videos/movies. When a file is deleted from the particular storage device, it is not permanently deleted from the hard drive,instead of it only the address location of the file is deleted. Thus making space for allocation of new data.I would strongly recommend you to use Remo recover (Mac)- Media Edition software as i have already undergone the same situation and successfully recovered all my deleted Mac files.
You can even download the demo version of this software and check for recovery result. Give it try. All the Best.:)
You can also follow the links given below:
1)https://www.mac-file-recovery.net/deleted.html
2)https://www.remosoftware.com/remo-recover-mac.zip