[Gameplay] Elise Spider Swarm Buff (# of spiders) not showing up sometimes

When playing as Elise, usually there is a buff icon for Spider Swarm that indicates how many spiders you have. Sometimes it's not there, so you would have to transform into spider form to see how many spiders were there.

How to reproduce: Play as Elise, pretty much.
(I recently played her top lane and jungle on summoners rift intermediate bots. However, thinking back, it seems to have been a problem before.)

In the most recent game, the buff was not present at the beginning of the game (even though I had 2 spiders). After my first trip back to the fountain, the buff appeared. Intentional?