To want to charge for the extra kid?

This happened to me when I was an au pair and I was furious. Just because you’re looking after one set of children doesn’t mean another one won’t be troublesome or extra responsibility. It could end up being really hard work if they fell out or were badly behaved or demanding. I would be asking for an additional 50%. Don’t do it free as you’ll be having them all the time.

Hmm if you babysit regularly for them and this is a one off I would let it go ( also you might get a lovely tip at the end)

If it does happen again after tonight then you need to have some sort of pricing in place for such occasions

2 families. Time and half
So £18

Both families pay £9 so they save £3ph

It depends whether they asked you to watch the extra child in advance tbh. If they did, then you had the option either to accept the job on that basis or decline it so they could hire another babysitter. If they're springing this on you, then that's unfair.

Personally I don't think it's cheeky to ask a babysitter to look after 3 older children from two families for one night so long as it is made clear in advance that this is what is being paid for, but obviously I'm in the minority here.

Of course not!

OP has agreed a charge and decided that's it's financially viable.

You wouldn't agree to do anything and then allow yourself to be out of pocket because they've changed the job!

Oops, missed that. I would be fine with this then as long as they know that they can’t get 2 for 1 babysitting every time.

The first post says the parents are all going out together.

They are taking the piss.

The other family should have got their own babysitter.

and as they haven't, make sure you let them know in advance that you won't be doing this for free.

the reply from @OliveWah is good !

An extra 10 year old is hardly going to be a challenge. If you had said an extra 2 year old, I would 100% agree that it was worth a higher hourly rate, but at that age how much babysitting do they really need.

Do you charge more for a family with 3 children vs 2 children? If so, apply the same model.

Message them and ask if the other couple wants you to bill them separately or if they will be paying together.

That way you're making it clear there's no question that you expect to be paid for all the children you will be responsible for.

They can't possibly have assumed you would just do it for free, right? 🤷

They should be paying you extra. £12 per hour seems very low to take in an extra child. It's a bit cheeky.

I would charge a small supplement, they're robbing you or another babysitter of custom purely for their own convenience, I think it's cheeky.

You should absolutely ask for more.

They may be splitting the cost between them and benefitting them that way.

Text them your combined rate now.

Going anywhere nice tonight? 😄

If these are regular clients then I’d let it go this once, but make it clear to them so it’s not a repeat occurrence. Something like “thanks for letting me know. Normally I’d charge £X amount more for 3 children not 2, but for this time I’ll keep it to the normal price”.

id be more worried about whether the friend’s parents knew that the parents are going out and being looked after by a babysitter. Nothing against your work OP I just like to know who’s responsible for my child!

I would ask the parent who usually pays you "Is the new child's Mum/Dad paying me separately, or are you paying all together?", which indicates to them that you are expecting to be paid more than your usual 2 child rate. I would expect around £15ph for 3 kids, so an extra £3ph. Let us know how you get on!

If the kids were toddlers charging more would be reasonable. At ten I'm not so sure. It's not really extra work.

I’d charge more for a sleepover supervision than a straight babysitting and I’d need phone numbers and any relevant info on the third child. In this instance I’d text back and say you normally would charge more for this situation and want to talk to the other parents but you can do it tonight.

Did they ask you or tell you?

a nice ask and maybe I would let it go as a once off (and phrase it that way)

if they just told you, then they can be told right back that there is an extra charge for more children, especially if from another family

I would expect to pay more for an additional child. Not sure about going rates because we don’t need sitters at this point, but definitely more.

I’d explain the rate I’d quoted was for 2 kids and add some extra on.

I wouldn't bother no.

I would be worried about setting a precedence and would definitely have a rate for one family versus two. Maybe 1.5x for two families? They can challenge you on the logic about child numbers if they want but those are your terms they can take or leave.

Unless the other person is you how can you possibly know that?

You must not have been on here long if you think CFs dont exist

The other family should have sourced their own babysitter.

Are you now the default babysitter for their friendship group any time they all go out?

I would tell them the cost is now £16 per hour. Still cheaper than 2 babysitters.

You have 3 kids to look free.

Only difference would be if they were all already asleep.