What can I do to keep them entertained?

So I'm babysitting my sister's 4 kids next week. I typically babysit once or twice a week for her,and I do it as a favor (no charge) and it's only for up to 4 hours at most. This time it's going to be different because she's going out of town for two days, and I'm going to be left in charge of them, for a half day, one whole night, and another day from morning to midnight.

My question is : what can I do to entertain the kids for so long? I mean when I babysit for a few hours, I usually just do fun things like create forts, or let them do my makeup, but that's only for a little while, this time it's going to be for a much longer period, and it might be a challenge.

Ages of the children are two girls (8 mos., and 3 years old) and two boys (6 and 11)

Can anyone help me out with some suggestions?
or give me a list of some items I can purchase that will help me out?

[weeniegeniewife]

Hi, and welcome! We would love it if you would post in the introduction thread so we can get to know you a little better. I'll let the others who have young kids answer your ?.

[metroguy]

focus on taking care of the 8 month baby. the 3/6/9 will play/fight with each other. if they play--it's easy. if they fight, it's hell because the 8 month baby will be crying like crazy.

[kentovellq]

Don't give everything at once. When you give them make up, give them lipstick first, then add the mascara after then add another make up after a few minutes.