Can anyone explain this?

We have a full bathroom on the 2nd floor, and directly underneath on the 1st floor is a half-bath. Last night, a bath was taken in the upstairs bathtub. After the bath, while the tub was draining (pretty sure it was actually a minute or 2 after it fully drained) HUGE bubbles were coming from the downstairs toilet. It made a loud Glug-Glug-Glug sound about 15 times, then stopped. After this, that toilet would not flush. It behaved exactly as if the toilet was clogged - the bowl just filled up with water extra high, almost overflowing. I held up the float and the bowl did drain, although pretty slowly. After doing this about 3 times, the toilet finally flushed 100% normal. The toilet has been flushing normally for 24 hours now. Another bath was taken (in a different 2nd floor tub, 25 feet away, same exterior wall) and everything has been fine.

[Another data point, the 1st bath that caused the “clog” or whatever, an s-load of body wash was used, like 1/2 a bottle (kid playing with it.)]

• Should I get someone out to look at this?

• Can anyone explain wtf happened?

Thank you.