Artificial intelligence (AI) has demonstrated significant potential in supporting pediatric speech therapy. However, no systematic review has examined the quality and expanding landscape of commercially available AI-enabled speech therapy mobile apps for children. We conducted a systematic review and analysis of 21 identified commercially available AI-enabled apps designed for speech-sound practice with children. Using 15 evaluation criteria consolidated and extended from prior HCI design guidelines for human-AI and child-AI interaction, our content and risk analysis revealed that existing apps have not yet leveraged the full potential of existing AI tools, and often fail to rigorously adhere to the best recommended practice. Incorporating feedback from the speech therapy community, we categorized our findings into four areas of ethical concern. To address these concerns, we propose actionable recommendations for app designers, families, and speech therapists to guide more ethical development and safe use of AI-enabled applications for pediatric speech therapy.