You can choose your favorite child to be your next generation. Give him two or three encyclopedias after turning the oven on. For example, if you want him to be a cook, start giving him the cooking books after the encyclopedias. When you start the new family, he will not only be a cook, he will be in level 6 in less than 24 hours. If you do not give him an specific book he will become a Rocket Scientist, earning 105 Novice.