that's kind of mean, don't you think ?
If you look at life like it's a gift, perhaps every day should be celebrated. It's not always the HUGE EVENTS in life that should be celebrated. Sometimes it's the tiny ones. I'll bet while getting into kindergarten isn't that big a deal to you, it's probably monumental to the OP's daughter. And the OP is probably not looking for YOU to congratulate her DD, perhaps she just wants her daughter to feel like her accomplishment IS special. And you know what ? It IS special and it IS important and shows what a great mom she is for wanting to make a big deal of it.
Maybe if you look around at the little things in YOUR life, you'll realize that tiny things should be appreciated and celebrated. Be thankful for life, and celebrate it. If you've ever been through a fight for life with someone with cancer, you realize that it is NOT the big things in life that should be celebrated and appreciated. It's every single tiny little thing.

Okay, rant over.