What would you say when...?

Hi! I was wondering what English speaker would say in this particular situation.
You have children and you take them to a daycare.
You want to show your politeness to a caretaker,
so you want to say little more than “Hi how’s it going?”.
Would it be something like;
“Sorry to give you much trouble.”
“I appreciate your kindness.”
I got asked this question by some Japanese people.
Maybe it is a cultural thing and you may not say such kind of thing
or you might?

Hi, how’s it going? Thank you for taking care of them for us. We appreciate it very much. Thanks so much.

ps. i think it is a cultural thing to not feel obliged to show your appreciation, but if you are offering pleasantries then something not too over the top appears to be well received (in my experience… although i don’t have kids, i’m sure i remember seeing such interaction in movies, tv, with other people’s kids etc).

Thank you, Roy!
I will let them know what to say, in the mean time it is not necessary in western culture.