My first cat Grisette was feral born and came in the house at about 13 weeks. She spent the first 3 weeks under the kitchen cupboard- and I must admit it was 30 years ago, so I didn't think too much about the problems that could arise.

She was absolutely tame and when she had kittens (At that time I thought she should have kittens one time ) she had them in the living room in a quiet corner and I could be with her I am so glad I had this experience.

I think everything will go fine with a little time and a slow introduction. All the best for your cute new addition.