Haha sibuk betul dia! Ya, benang yang lembut dan biru tu probably absorbable sutures, memang designed to dissolve on their own dalam few weeks, so tak perlu pull out manually. Kalau dia dah excited nak "explore" benang tu, just gently redirect la, tapi jangan kena koyak-koyak lagi sebab area tu still healing. If any part dah loose or suspicious, snap a quick pic and WhatsApp your pediatrician just to be safe, better safe than sorry dengan luka.