Earlier quoted context omitted.
In Australia roughly 20 kids per week present to emergency having swallowed or inserted a button battery and in several cases many have tragically died. It is an agonising death over a period of days/weeks for the child and horrible for the parents to witness. Many times both the parents and medical professionals don't realise what is actually happening to the child until it is too late. There is growing support for…
CR2032 is 2cm wide so you're probably referring to smaller batteries as these cannot be swallowed by a child.
Children can easily ingest objects 2cm in diameter, and batteries that size can be especially dangerous because of how they lodge in the esophagus.
Citing Eck, Langham says, "Clinical outcomes can be determined by assessing the diameter of the button battery, as 90% of all major or fatal outcomes are associated with lithium batteries of 20 to 25 mm in diameter"
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7536469/