She was on top of her cage, while I was in the front yard working on a project. The sliding door was open about 3-4 inches, enough to fit her muzzle through. I guess she slid the door so she could get through, and probably spooked Yoshi. It was a careless mistake of mine to leave her out her cage unattended. Unfortunately, I have learned and I hope that everyone who reads this also learns from my terrible mistake. Thank you all for the kind responses