Practical yet stylish bag for days out with the kids

[LMonkey]

Looking for a bag for when we're out with the kids but without the pram and changing bag - basically a bag for everything we need for our 2.9 yr old and 6 month old combined with a handbag for me. Needs to be roomy enough to fit in a couple of nappies, wipes, snacks, my phone, purse etc etc. BUT I would like it to actually look nice as I do worry that I'm getting a bit too mumsy (!). It would be worn whilst I have the baby in the carrier. Does such a thing even exist?! Would love to know what bags you ladies use/have seen which you think fit the bill. If you can post links that would be excellent too!

Should add that I really don't want to spend more than £50 on it, ideally a lot less. Just to make things even more tricky.

I use a brown leather backpack handbag when I have the carrier (lots more backpack handbag styles around at the moment) and have a Kipling bag that fits over the handlebars for when I have the pram. Both fit wipes, nappies, babygrows, purse, little brush and phone easily.

Thanks daisy ,that's the kind of thing I had in mind. If anyone's seen a good one do let me know!