There is a similar answer to both of these questions. Your child’s development, and therefore multilingual development, depends on many different factors such as: How long has your child been attending kindergarten? How long have they been in contact with the spoken languages? How much contact with the new languages will he or she have outside the kindergarten? All of these factors make a difference.
In principle, the more intensive contact your child has with the new language, the faster he or she will learn the language(s). Another important factor is the course of language development and the character of your child. At first, a passive vocabulary (the “understanding“) will always develop before the child has the courage to actively experiment with the new language. This takes different lengths of time depending on the child's personality. Our experience spans the spectrum and we are very committed to supporting your child individually, and the joy of learning comes first for us.
If you would like to support your child in learning a new language in addition to preschool, we also recommend language contacts outside of school (e.g. baby-sitter or sport/art classes in the new language). We are always happy to have additional conversations with you about how to best support this.