We got a big wide Ryco one. It has a front pocket with compartments, a bottle warmer hole, a big slide zip and a change mat attached to the back. DD1 was only 21 months when DD2 was born so it meant lots of nappies. I think I just got it from Target or Kmart and it has plenty of room for 2 kids stuff. DD1 still uses her Barbie bag whenever she goes somewhere by herself like daycare, so I just keep a spare change of clothes and a couple of nappies with a small pack of wipes in it.
I dont have 2 kids but instead of spending heaps on a "nappy bag" we just bought a slazenger sports bag for $20 (reduced from $40 ). It's huge and fits plenty in, the only problem is because there's so much room I put in more stuff than we need
RE your DS's bag: you could just let him take it with a couple of things in it and if he doesn't want to carry it, it'd probably fit inside the other bag. Or use it as a lunch bag?
I have found it to hard to take nappy bag with 2 as I have phil and ted pram and it hits 1 of them in head and is just in way, so I have just put change mat, nappies for both, wipes, DS1 drink bottle and snacks in a canvas bag and shove under pram.
my age gap is only 21months so we've still got a way to go with both in nappies, so I got myself a bigger bag - its an oioi one and fits cloth nappies for the pair of them for the day, but then i normally take a little esky with snacks for dd.
maybe keep the bob bag for your DS, and then just get a smaller bag for the new baby - when it was just DD, I got a gorgeous petunia pickle bottom tote bag, which was spacy enough for a couple of nappies and snacks. The other thing you can do is cull what you actually keep in the nappy bag to make it less bulky - I remember when I went from a bigger nappy bag to the smaller one with DD, I cleaned out the big one and the majority of the stuff in there never got used.
I think the others have a good solution here - let DS carry as much as he can in his little bag, and carry the rest in a bigger nappy bag. I wonder if there are bags where a little backpack can zip on and off? That would be ace.
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