My Meeko did that when Yoshi was born. I would hold her and put him on and she tried to leave. The next day we called the Vet and they said to bring her in. She felt hard on the side and we thought a kitten was still in her. They did a Xray and it was all Constipation. Coco and her kitten were in the same room as Meeko and she would try take Yoshi so he can nurse on her but Meeko would stop her. Meeko did let him nurse later on but cut him off at 8 weeks. He also nursed on Coco. Your Cat might let them soon.