Probiotics for children?

[Sops]

Has anybody had any experience of using probiotics for kids?
My dd is six now and she hardly ever has a solid poo (sorry for TMI). I wouldn't say it was diarrhoea and she is other wise very fit and healthy- she's never had a day off school yet.
The only issues she has ever had are recurrent ear infections (which she seems to have grown out of now), she's had a fair few bouts of antibiotics for these and she did have Kawasaki disease (causes inflammation of the blood vessels) when she was six months old and spent a week in hospital.
At first they misdiagnosed the Kawasaki as a urine infection and gave her a pretty hard core dose of antibiotics (which of course had no effect on the Kawasaki).
My hypothesis is that maybe her gut has too few good bacteria (all killed off by too many antibiotics) and is therefore a little imbalanced and might benefit from probiotics.
Anyone else had any experience of using probiotics for children. Should I use a supplement or buy yoghurt type drinks?

Forgot to say she eats very healthily so I don't think that her diet is an issue here.

The yoghurt drinks are pretty useless in terms of repopulating the gut, I was recommended the Solgar or BioCare powder which you mix into yoghurt or juice.
Click here

Just for info, apparently by the age of 5, there are a similar number of gut bacteria needed as that in an adult.

We have had a probiotic from Gt Ormond Street Hosp for dd2 - I think it may have been a trial, its not widely available.

I still don't believe they work - you are better to eat the sort of foods that the healthy bacteria need to flourish - fruit and veg. Your stomach ph is about 2 so will kill the vast majority of bacteria you eat, whether probiotic or not.

I have used Bio-Kult for my ds, have a look at the website as it's best ever info I have found (plus the book is also great).

I have been using bio-kult for ds following food doctor talk recommendation at work. I remember them saying the probiotic yoghurt were less effective as they had a high sugar content. The capsules can be easily cracked open & sprinkled into organic yoghurt.

If her poo is regularly really lose, maybe worth getting it checked out?

Sops, have you ever seen Bristol stool scale ?

It is what doctors use to assess bowel movements.

Thanks everyone.
On the bristol scale she is scoring 5 and 6, I can't recollect a 4 tbh.
She has a very good diet (certainly better than a lot of her friends) and is a good eater of fruit and veg. I try to keep an eye on what both my two eat and I reckon it's pretty healthy- brown bread, wholegrain cereals, veggies galore, water to drink, as much home cooked as I can manage, sweets and crisps just as a treat. I don't think she's overdoing the fruit either.
She did have a few bad episodes of constipation when she first started school, the doc prescribed Lactulose, which helped but the constipation only stopped when she stopped having school dinners. I guessed that the increase in refined carbs compared to home diet (they seemed to serve up lots of white bread and traditional puddings every day) was the culprit and a GP friend agreed with me.
I really can't think there is that much room for improvement in her current diet which is why the thought of probiotics popped into my head. Ds obviously eats exactly the same diet and his bristol scale score is a consistent 4.
All I can seem to find on these issues keeps coming back to diet as a cure all but I wonder what else I can do. Maybe I do need to see GP but I will feel a bit of a fool saying she's perfectly healthy, maybe I'm over-analysing?