Am I Able to Have Invisalign with a Permanent Baby Tooth?

Permanent retained baby teeth are ankylosed to the bone meaning they are fused there. They cannot be moved by anything. This does not affect your invisalign though because the aligner can still fit over it with no problems. If the baby tooth is crooked then it needs to be pulled first before the treatment, but with invisalign they can add a fake tooth into your aligners to cosmetically cover the gap until you can get an implant and crown.

Yes, you can still have invisalign with a primary tooth, but it is advised not to move that tooth. Invisalign is a great system because you can make it so that the primary tooth does not move while the other teeth will move.  If you want to move the "baby" tooth, then there is a high chance that the tooth will become immobile and unstable.