My SIL is Japanese and my niece speaks Japanese and English beautifully. It's great as when her Grandparent come for a visit from Japan they can talk and they have a wonderful relationship. It was funny when she first started talking as she would tell my brother off in Japanese and he would have no idea what she was saying. She also speaks Japanese to her mum and english to everyone else. My mum was being taught Maltese by her father when she was young but her mum put a stop to it as she didn't understand what they were talking about and got angry. I say go for it - I'd love to be able to speak a second language - if only I had been taught at a young age (I did 2 years of French at high school and learnt how to say 'horse' I just didn't have an interest at that age! - oh to have a crystal ball). Do it while the bubba is young- before they have a mind of their own!