Yes, it is. She is exploring her self and developing motor skills and coordination and it is a way for her to self soothe. I generally don't pull her hand away, but I gave this wrist rattle for her instead as I also do fear that she may chew and injure her own finger! She outgrew this completely at around 8 months. https://www.amazon.com/Lamaze-Gardenbug-Wrist-Rattle-Finder/dp/B00R7Q2RVK Saw Mothercare Paragon selling this item as well.
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