PLease please be very careful about giving soya milk to very young children as it contains female hormones which can have a long term detrimental effect. (according to the nutritionist I consulted about my dd's problems) I successfully bottle fed my daughter after the age of 12 months on Rice milk with added calcium (made by Rice dream some supermarkets sell it and most health food shops sell it - if not I can find the suppliers name and number if you need it) pre 12 months after I had stopped breast feeding - I discovered 'Babynat' which is an excellent formula which is french and has mainly vegetable fats to provide the fats intake and I think it was goats or ordinary cows skimmed milk powder and didn't have too bad an effect on her.
Cheese is a big bad culprit re mucus production as it is hard for the body to breakdown so keep it to a minimum. I used to sprinkle crushed sesame seeds (not tahini it is foul!!) onto my daughters cereal and into bolognese sauces etc you need c 6 teaspoons a day in their diet. The recommended dosage of 'typical' dairy intake is 800g but with non dairy as it is more easily abosrbed this can be reduced to 600.
Broccolli, caulifower is great for calcium as is parsley - the best source of calcium ever and easy to hide. Sunflower seeds - lakeland sell 'munchy seeds' which are delicious as a snack and full of calcium or can be eaten on bread and butter as a crunchy sandwich!!
I had real problems with my daughter up until 20 months and after she turned 2 I dropped the rice milk completely and she just has fish (tuna pasta) 3 times a week, yoghurts, occasional cheese and ordinary milk on her cereal without any problems at all and she went through an awful, couldn't breathe and was always sick phase when doctors diagnosed and treated her for asthma - she shows no signs of this now at all.
One last note - if you have a bunged up child, avoid bananas they are a big 'mucus' producer - so take the strain off their little systems. Good luck in your reduction of dairy it is not as essential as people think and I think it does a lot more harm than good. But dd has grown out of her 'intolerances' and is a happy, healthy child.