Worried that Aldrin might make trouble, Camila whispered into Isaac's ear, "Aldrin's also here. I'm afraid that he'll try something, so I'm going to go and find him

Isaac nodded and whispered back, "Be careful."

His breath tickled her ear, making her heart skip a beat. Although he only said two words, she felt touched.

It turned out he still cared about her.

Even though they were separated because of Cathy's death, he still cared about her.