Deep end of most little pool is 8 feet. I doubt it was like a big swimming pool a 25 m one.
Sorrie to hear he drown but to drown in 8 feet? That's only 3 feet higher than alot of hmong people.
I always tell everyone the main thing is to relax. You know you can hold your breath for at least 30 seconds. In 30 seconds, that's more than enough time to hold your breath and work your way over to the more shallow end.