In case anyone is curious, this source does claim that "lap infants" are more likely to be injured than other passengers. But the article defines "lap infant" as anyone under 2 years old, regardless of whether they were in fact in someone's lap. (In particular, some of these "lap infants" fell from the cot!)
Potentially worth quoting as well: "Scalding burns from hot beverages or soups spilled over a child during hot meal service were the most commonly identified mechanism of injury".