We left LO last night with the grandparents for a long time (5:30pm-2:30am). We did a dinner a few weeks ago but it was only about 2 hrs.
I was nervous that she would fuss a lot or hate the frozen milk I left.
They said she did really well. I left 12 oz of milk just in case and she only drank 6oz. They said she snuggled and slept in the swing the entire time and barely fussed.