hi, i have a 15 month old girl and put on 30kgs trying to get it off,
i recomend eating 5-6 meals a day i know its hard!!! but have breakfat then an apple with a slice of cheese, lunch(salad sandwich with cheese or meat), then a snack with some sort of protein (egg or lean ham) then dinner of lean meat and vege.. and if you need something later a snack of nuts etc... plus at least 2litres of water a day (over the day not all at once) remember small decent serves of foods. calorie king website is also quite good and free!!!
also grab 2 cans of baked beansor cans of anything soup/ tomatos (start with 400gm tins and we will ork p as your strength improves) and do some arm curls, side lateral lifts , squats with arms out front and lunges... just some simple weight bearing exercises in conjunction with your step exercises. make sure your step exercises are getting the heart rate up and that you feel puffed and cant hold a conversation.
hopefully this will help to jump start your metabolism and by doing the weights you will create lean muscle which will help you loose weight!!!!
good luck and if you have any questions yell out!!!!