Inch Bodyboard

What is the best bodyboard for little kids? What size?

I have two 4.5-year-old kids who just learned how to catch a wave in the Gulf with a cheap Pool Raft. They saw the other kids using bodyboards / boogie boards, and have requested their own. My boy is about 38 or 39 lbs with a sturdy build, and my girl is about 30 lbs with a tall, skinny build. I don’t want to spend a fortune, but I want something that won’t break right away. What size do I buy for each of my kids? 33 inches? 27 inches? something else? Are some brands better for beginners or little kids? They will be using this in small waves under adult supervision of course. Thanks.
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