Employee's biggest out burst yet?

We recently hired a new employee in our shop. For context there is only 3 employees at this location and we work in close quarters, we have to interact a lot. They started as a temp but have now been fully hired. When they were a temp they were normal and easy to work with but did have a moment where they trauma dumped on us and the other temps. We did not think about it as anything serious, more as a way to connect or vent due to not having friends possibly.

Fast forward three months later they have had multiple small awkward incidents including having moments of intense forgetfulness, oversharing, and inconsideration of us. But today feels like it is the straw that broke the camels back when they fully started man handling the product we were stocking and then turning to us and sobbing saying there was too much stress on them from a situation with their mom and they had to go home. In an uncomfortable reaction we told them we had it covered and to just go home. We were aware they were having to visit their mom that weekend and seemed to have been dreading it . For context their mom does have dementia and they have been dealing with all the logistics of her care.

So the situation is one of us has recently become a lead and is unsure on how to handle the situation. Higher ups will most likely see this as a non issue due to lack of actually ever being at this specific location. For context me and the other coworker are friendly and have tried to be friendly with the other coworker who had an outburst but it feels impossible and overall uncomfortable due to the trauma dumping they do.

What can be done after this ? Should the lead have a serious talk or just check in with them? Or leave the situation alone as a whole until said coworker talks about it? When is it too much emotionally in the workplace? We will not see this coworker until Monday. We'll answer any questions for any more context and wanting to just hear an unbiased opinion thanks.