How and When to Introduce a Second Language

Our 10-month-old daughter is just starting to say "mama" and "dada." My husband and I both come from Spanish-speaking countries. Now that we live in America, we want our daughter to be able to speak both languages fluently. Our questions are: How do we do this without getting her mixed up? Should we teach her one language first and then introduce the second language? Which language should we start with, or should we teach her both languages at once? -- Two Languages
Answer: Being able to speak both languages will definitely benefit your child's intellectual, cultural and economic future. If your daughter has been hearing both languages, she is well on her way to learning each one. When children pick up two languages before they are 3, one language may dominate at times. Research shows, however, that early regular exposure to two languages allows most children to successfully become bilingual. There is some disagreement about whether bilingual children develop vocabulary slower than those who speak just one language.
If you wait until after your child is 3 to introduce a second language, she still will become bilingual. She will have a greater vocabulary in the first language for some time. Plus, she will have to learn the grammar, structure and vocabulary of the new language. At first, errors in usage will occur. She also is likely to use both languages in a single sentence.
If you elect to start your daughter on the road to learning both languages now, she will need to hear each one frequently in order to acquire sufficient vocabulary to speak them well. Use both languages in a natural way in your home. It's also a good idea to read books to your daughter in both languages. This will further expand her listening vocabulary in each language.