So she wasn't really worried about it in terms of right or wrong - that wouldn't have mattered much anyways. When someone accepted Islam into their life, their previous sins were washed away. She was mostly worried about Amaar. Samirah felt for Ariadne, though couldn't quite put herself in her place.
"I think being honest with Amaar is the right thing to do. I don't think he will judge you for it and I think lying would hurt the relationship you have together." Samirah usually thought the truth was the most important, even if she very rarely brought up her parentage.