Merging a mirrored object with a normal object + rigg without possible?

[Peetzii]

Hey there!

I have two questions.

1. I was modelling a spider with the head as an sphere and the legs as an seperate object which got mirrored - can i combine them somehow ?

2. Can I rigg the spider with those 2 seperate objects or does it have to be one whole object?

Thanks in advance :]