Recreational & Family - Question about bicycle saddles for children.

I bought a second-hand tandem this week, and it's a lot of fun. I've been riding it alone and with my 9-year-old daughter. We've also pulled our trailer with the two smallest children, and I may add a trailer bike before the trailer for my 5-year-old, who's competent enough, but a bit slow--although he's been riding his sister's 16" wheel bike recently, which is noticeably faster (and he seems to be a bit less stable than on the smaller bike).
My daughter really seems to like riding the tandem, but says the seat is uncomfortable in the front. It's a wide, short, rather padded (but I usually ride a Brooks). I tried different angles, and tilting it back a bit helped some, but not enough. I also put the seat from her 20" BMX bike on, and she still felt sore, although she might simply have been sore from riding the other saddle for a few miles. Is this an adjustment problem, or should we try a different saddle? I aim to try her again on the BMX seat after a day or two.
Do any of you have experience with children's bicycle seats? Are higher quality ones with any attention to comfort made? And, generally, do children need smaller saddles, or would a good quality adult saddle be best?

It's hard to find good quality kid specific saddles.

I can only suggest as you are doing and that is to retry her BMX saddle after she has had time to heal. It is not uncommon to have difficulty setting up a woman to ride comfortably. Kids are typically easier, but I am not surprised by the fact that it is your daughter that has discomfort. I'll assume you have the saddle adjusted as she does on her regular bike. That may be for naught if you can't get the the handlebars into an approximate position. She may be a bit stretched on the tandem.

Hopefully you'll find a setup that works for her.

I have found that pair of bike shorts will do wonders for a kid. Mine have started on Trail a bikes at 3, so padded shorts weren't really available. So they just wore close fitting spandex bottoms, without underwear and that alone has gone a long way to getting/keeping them comfy. At 9, you should be able to find a decent padded pair in her size.

We also found that a small womens seat, with a cut out seemed more comfy than the standard kids seats. I haven't found a kids seat that seems to be comfy in the long run for my kids. I suppose there might be an option, but I just haven't found one.

Is she able to stand up as she pedals. We encourage ours to stand up often and than helps to cut the constant pressure. I think that kids tend to just "sit" the whole time and not realize that you really should lift off of the seat. We do a lot of taking turns standing and kinda make a game of it to really teach the art of letting that tush breath

Thanks.
I fitted a cheap seatpost with the clamp flipped upside down, after finally finding a shim that would make it fit right (and thanks to Sheldon Brown for the idea). While she could reach the pedals before, it was just barely. The extra inch seems to make a difference in, as the previous post says, taking some pressure off by holding more weight with the legs. She seems reasonably comfortable now, and never complained about the seat when it was on her BMX bike, even after a couple of hours (with occasional rests). If it starts being a problem, we could try a new seat, adding another 3/4" by putting boards on the pedals, or else buy crank shorteners. I found some here: http://www.pediatriceshop.com/reha-partner-crank-shortener.html?___store=pediatric that seem more affordable than most.

The crank shorteners look like what you need. I expect a crank length between 140 and 150 would fit her legs.

I called on the crank shorteners that you listed. They will not sell them to you unless you own one of their bikes and must provide the model number to prove it. I spoke with a nice gal who said she did not think they would fit a different bike as they don't fit the other types of bikes they sell, but said the company restricts the sale. Let me know if you find a comparably priced option