AUTHORITY: About KidsHealth (bottom) says its part of Nemours. Info on Nemours appears on page. There's link to experts who review materials. High degree of authority.
CURRENCY: 3 main sections of site show copyright 2017. Individual articles show date they were reviewed. Also, About page says: "Ongoing... reviews ensure that information is as up-to-date as possible."
RELEVANCE: Covers many important aspects of child/teen health, from different points of view. Highly relevant.
ACCURACY: Accuracy and authority are linked. Site is accurate.
BIAS: About KidsHealth says it's unbiased. Don't see mission statement. But I don't detect bias in reviewers or articles.
VERDICT: Trustworthy. Suitable for research and personal use.