Why is there orbs on my pictures?

I usually take pictures of anything and everywhere, inside and out. But every time I go to my moms house I see orbs in almost every picture. Some may come with over 20 and some with just 1. Some seem far away and some very bright and near. I would keep the camera steady and the orb moves like its just flying. There's even pictures where you can kinda see faces but Im scared to even pay close attention. It does not look like dust or water. And this only happens at my mothers house inside but more outside.