The school very well could have other numbers to try in the event of an emergency, and might well have tried those numbers -- IF -- they viewed the child's absence as an emergency.
How does your kid's school define "emergency"? I suspect at most schools, an emergency is something like:
- the child is hurt on the schoolyard, or in an science experiment, needs medical attention.
- child has an asthma attack, needs medical attention
- school fire
- shooting at the school - locked down - must alert parents
The thing is, how many schools are going to define a child not arriving on time as an emergency? Odds are the staff making the calls to parents on absent kids, who's parents hadn't called in to say their kids were not coming did not deem an absence from school as an emergency.
Its possible this kid and her family is well known at the school - maybe she had the sniffles the day before and they all just thought she wasn't feeling well and mom had forgotten to call it in?
I doubt most schools would deem a kid not showing up as an emergency - if they did, they'd be making a lot of emergency calls to parents and extra contacts every morning.