I surrender to craziness

Not a good morning.  Kids up early and fought with each other all morning.  I just wanted to be the fun grandmother.  I love them dearly but helping my son raise them is exhausting.  I was overwhelmed by 7:30 AM. I breakdown which makes things worse.  The last straw was the temper tantrum over chips.  Chips for breakfast.  Then their father comes home calms everyone and gives them chips anyway.  The 3 and 4 year old at daycare and now I just have 1-1/2 year old and it seems like a piece of cake.  Mostly I just wanted to be the fun grandmother.  I hate the way things are right now.  I want to protect them but I'm overwhelmed.