That was one of the hottest games I've ever been at in LES, all of the Powerade was sold out by halftime, wife and I both got sunburned.
Some guy 2 rows in front of us has his newborn baby (definitely less than 6 months old), talking about his kids (all named after BYU players) and how his very first game was when he was 6 months old so he had to do the same for his new baby. The heat was sweltering for the adults, just couldn't bear to watch this newborn baby sitting out in the sun like that.
Other than that, don't usually have a problem with it if they're well behaved - but definitely not something I'd do myself.