First Overnight, HELP!!

Hi guys , so I live in Texas . The family I am working for currently is expecting a mother child on the way so I'm set to work overnight when the mother has her baby .
They have a two year old boy and I can't for him 3 days a week from 8am-6:30pm . I get paid 11 an hour , but with this overnight I have no idea what to charge.
We figured a flat rate would be best since we don't know when she's going into labor. What do you guys think would be safe bet ?
The thing is he is two but he doesn't sleep on his own so he would be sleeping with me and he doesn't sleep through the night . He's a typical terrible two, super attached kid . My original plan was to charge 150 for the the beginning of the day until the next morning and then charge an hourly rate if I'm there past 12 in the afternoon, since it'll be a new day.
What do you guys think?
I figured whether it be I went in early in the day or late 150 would be good base since he doesn't sleep through the night and I'm going to have to be on call the next two weeks until the baby comes.

Comments

For overnights, you charge your hourly rate until the kid goes to sleep then charge an overnight fee to sleep there. The fee varies, but somewhere around 100-150. Dont just take the flate fee

I charge $120 from 7pm to 7am. That is for a family whose baby goes down at 6:30-7:00. Then my hourly rate outside of those hours.

I always charge a flat rate of $150.. for overnight.. Then starting the next morning charge by the hour.. $11 is ridiculous ... The more experience the more you can charge..I make $36 A hr.. Good luck..