Need help identifying a rescue plant

This is a rooted piece of plant that a coworker would like me to bring into better health & appearance, but I have NO idea what it is!! He called it a Gibraltar cactus, but I think might be just a family nickname for it, because that doesn’t yield any likely results in an internet search. Will you help identify it please?
Thanks!

Hi Lisa,

Your plant looks like a Crown of Thorns (Euphorbia milii)

Red flowers on Crown of Thorns

Crown of Thorns Plant

Here are some care tips:

A Crown of Thorns Plant is a poisonous houseplant with a level #2 toxicity. Broken or damaged leaves and stems ooze a milky latex substance that may cause blistering and pain if you have any open cuts. If a child or pet eats part of the plant, severe mouth irritation, gastro- intestinal problems, and even hemorrhage can occur. Read more about common houseplants that are poisonous in Don’t Feed Me To Your Cat! A Guide to Poisonous Houseplants