So I've had Blender for years now but I'm still a noob at it. I made a bipedal model, an armature, and weight-painted it in Blender 2.7. I then figured it was about time to update it to 2.9. After I did that, I can't see my armature anymore! I have tried Unhiding everything with Alt-H, clicking around the Outline, toggling the X-Ray for the mesh, fidding with Viewport Display settings in Properties, but nothing seems to be working. It is such a simple thing yet I've spent literally an hour trying to figure it out, and I am getting really frustrated with myself. Thank you for your help!
The armature I want to be visible is Penguin>Skeleton
Edit: Here is a link to my .blend file: https://drive.google.com/file/d/1darEP59YbALtv4lqDqYXXS6K270zA3_n/view?usp=sharing