How to securely share a link to a video on my server

I’ve created a web system for daycares on which the educators can upload videos of the kids, and then share those videos with the parents.

Currently the way I’m doing this is very simple. My system generates an email (to the parents) with a link to the video where it resides on my server. The educator clicks a "Send" button and the system fires off the email with the link.

For example:

The video is not password protected, but the video name is randomly generated so impossible to guess. My question is, is this a security risk? And if so, what would be a better way to share these videos?