Black ant bites

My one year old sat in a black ant bed I didn’t know was in our garden. She is covered in bites. We used the bug bite thing on as many as we could and slathered her in hydrocortisone. Is there anything else I can do? I had no idea they would/could bite and I’m so sad for her!! The worst area is one of her thighs, it’s just a giant cluster I couldn’t even tell one bite from another it is just all red and swollen and getting warm to the touch. Ugh. Parenting fail.